Human Bio Blog

Unit 4 Ethical Essay

2008-12-13T06:20:00.000-08:00

Is population growth the cause of decreasing resources? It very well could be, but there are other factors that need to be looked at before we decide. The growing number of the world's population could be depleting our resources, or it could be the massive use of resources by humans in the more developed countries.

One hundred years ago, in 1908, the world's population was 1,720,300,000 people. In the year 2000 it had jumped to 6,045,955,000. That shows enormous exponential growth. And of course, the more people there are, the more resources are used. Human beings need land, water, food, and energy. More and more of those resources are being consumed everyday. However, as technology increases, new ways are being found to supply more and more resources so we do not deplete our current supply. In a way, it kind of helps balance out, though there are still some resources that are in danger of us having a shortage.

A typical U.S. child will consume the same resources as 30 children in India and 300 children in Ethiopia. I got this information from our assignment page. This statement is actually quite alarming and has a lot to say about the more developed countries. We are so used to having access to resources that we over use them. They have become a commodity, and are taken advantage of. People in the more developed countries use an astonishingly higher amount of resources, which causes depletion of resources.

I think that both population growth and overuse of resources are the problem.

Unit 4 Main Lab

2008-12-12T19:17:00.000-08:00

1. Tree in courtyard outside our house. Salix Alba. This is a mutualistic relationship. We benefit from the tree because it gives us beauty and it benefits from us because we water it.

2. Koi in our pond. Cyprinus carpio. Again, a mutualistic relationship. We benefit from their beauty and they benefit from our care for them.

3. Pond scum. Cyanobacteria. Commensalistic...it's just there, it isn't harming the pond, and we do not harm it.

4. Water Lillies. Nymphaea. Mutualistic - Again, they provide beauty and we take care of them

5. Iris - Acorus calamus. Mutualistic for the same reason as the lillies

6. Clover, our pet rat. Rattus Norvegicus. Mutualistic...she gives us fun and companionship, and we give her food, water, and affection.

7. Raziel, my 2 year old daughter. Homo sapien. Mutualistic...I love her and provide for all of her needs, and get endless love in return

8. Bacteria in our mouth - caries. Parasitic...it destroys our teeth.

9. Spiders - archaearanea tepidariorum. Mutualistic...they eat our bugs, and they take shelter in our home

10. Dust mites - arachnida acari. Commensalistic - they are there and are annoying, but cause no harm

11. Humming birds. selasphorus rufus - Mutualistic...We provide them nectar, in return we get to observe their beauty

12. Crickets. Hadrogryllacris. Commensalistic...They pass through our house, and we help them back out the door.

13. Hornets. Polistes dominulus. Commensalistic - they are irritating, but will leave humans alone if they are left alone

14. Frog. Hyla arenicolor. Commensalistic - they hop around our courtyard and eat bugs

15. Bacteria on a piece of cheese - Penicillum roqueforte. Commensalistic...it is not a harmful bactieria

16. Bamboo plant - bambusa vulgaris. Mutualistic - it provides beauty, and we water it and make sure it has sunlight

17. Pomegranate - punica granatum. Mutualistic - humans care for the plant which in turn provides us fruit

18. Apple - malus domestica. Mutualistic for the same reasons as the pomegranate

19. Christmas tree, or Douglas Fir. pseudotsuga menziesri. Parasitic. Humans get to enjoy the beauty of the tree, but the tree dies because it is cut down. I wasn't able to get a picture of a real tree...ours is plastic :)

20. Yeast infection - candidiasis. My daughter had a couple of these as a newborn. Parasitic...it causes discomfort to the person, or host, affected.

Fertility Rate Lab

2008-12-12T19:13:00.000-08:00

The world fertility rate right now is 3.20.

My low fertility rate country that I chose was Canada with a fertility rate of 1.8.

Canada is a more developed country, and has a stabilized age-structure diagram. Population growth stays the same if couples on average have fewer than 2 children. Life expectancy is fairly high, which also helps provide the stability. There is an almost even number of females in the prereproductive, reproductive, and postreproductive phases.

10 things that describes a country with this type of growth rate might be :

balanced

good family structure

people survive long enough to see multiple generations

healthy

children get to be children

elderly are able to be cared for

healthy

good access to resources

organized

men and women are able to work

My high fertility rate country was Mali with a fertility rate of 7.30

Mali is a lesser developed country, with a low life expectancy of 45 years. There are many more women in the reproductive years and prereproductive years than those leaving them, therefore there are significantly more younger people.

10 things that might describe this type of lifestyle

1.crowded

2.children have to help out

3.women have to stay home

4.people do not live long enough to see many generations

5.limited access to resources

6. disorganized

7.poor healthcare

8. poor economy

9. diseases

10. struggling

Unit 4 Section 2 Compendium Review

2008-12-08T18:32:00.000-08:00

I. Human Evolution

A. Origin of Life

1. Primitive Earth

2. Small Organic Molecules

3. Macromolecules

4. Protocell

5. True Cell

B. Biological Evolution

1. Common Descent

2. Intelligent Design

3. Natural Selection

C. Classification of Humans

1. DNA DAta

2. Humans are Primates

3. Comparison of Human Skeleton to Chimpanzee Skeleton

D. Evolution of Hominids

1. First Hominids

2. Hominid Features

3. Earliest Fossil Hominids

4. Evolution of Australopithecines

5. Southern Africa

6. Eastern Africa

E. Evolution of Humans

1. Early Homo

2. Evolution of Modern Humans

3. Neandertals

4. Cro-Magnons

5. Human Variation

II. Global Ecology and Human Interferences

A. Nature of Ecosystems

1. Ecosystems

2. Biotic Components of an Ecosystem

3. Energy Flow and Chemical Cycling

B. Energy Flow

1. Trophic Levels

2. Ecological Pyramids

C. Global Biogeochemical Cycles

1. Water Cycle

2. Carbon Cycle

3. Nitrogen Cycle

4. Phosphorus Cycle

III. Human Population, Planetary Resources, and Conservation

A. Human Population Growth

1. MDCs VS LDCs

B. Human Use of Resources and Pollution

1. Land

2. Water

3. Food

4. Energy

5. Minerals

C. Biodiversity

1. Loss of biodiversity

2. Direct Value of biodiversity

3. Indirect Value of biodiversity

D. Working Toward a Sustainable Society

1. Today's Unsustainable Society

2. Characteristic of a Sustainable Society

3. Assessing Economic Well-Being and Quality of Life

One of the fundamental principles of biology states that all living things are made up of cells and that every cell comes from a preexisting cell. What produced the first cell? The sun and the planets probably formed from aggregates of dust particles and debris. The solar system was in place at 4.6 BYA. The Earth's mass is enough that the gravitational field has an atmosphere.

early Earth's atmosphere was most likely formed from gases escaping from volcanoes. It would mostly have contained water, nitrogen, carbon dioxide, and minimal amounts of hydrogen and carbon monoxide. The early Earth was extremely hot. As the Earth cooled the water vapor condensed to liquid and rain began to fall. It fell in such great quantities that the oceans were produced.

The rain washed other gases into the oceans.

The energy sources of primitive Earth would have included volcanoes, meteorites, lightening, radioactive isotopes, and ultraviolet radiation. This may have caused the primitive gases to react with each other and produce small organic compounds such as amino acids and nucleotides.

These molecules then likely joined together to become organic macromolecules. There are two different hypotheses that concern this stage of the origin of life. One is the RNA first hypothesis. This one suggests that only RNA was needed to progress toward the formation of the first cell. It was found that RNA can be both a substrate and an enzyme during RNA processing. The RNA is the enzyme. It is supposed that RNA could have carried out the processes of life that are commonly associated with DNA. The other hypothesis is known as the protein first hypothesis. Sidney Fox suggests that amino acids collected in puddles and the heat of the sun caused them to form proteinoids.

Cells have lipid protein membranes. If there are lipids available to microspheres the two become associated. This is how a protocell would have come into existence. A protocell would have been able to use the organic molecules in the ocean as food. A protocell would have been a heterotroph, or an organism that takes in preformed food.

A true cell is able to reproduce. DNA replicates before cell division occurs. The first true cells must have been prokaryotic cells, lacking a nucleus. Later eukaryotic cells would have evolved. Biological evolution is the process in which a species changes over the course of time. Descent from the original cell explains why all living things have a common cellular structure. Adaptation is a characteristic enabling an organism to survive and reproduce in the environment. Charles Darwin first formulated the widely accepted theory of evolution. At the age of 22 he sailed around the world on the HMS Beagle. The ship sailed the tropics of the Southern Hemisphere, and this is where Darwin began to realize that life forms change over time and from place to place.

The best evidence for evolution are fossils, or the actual remains of species that lived on Earth at least 10,000 years ago. Most fossils are found in sedimentary rock. Sediment becomes stratum, or a recognizable layer. Any stratum is older than the one above it, and younger than the one below it. When an organism dies, scavengers consume the soft parts. The fossils only consist of hard parts such as shells, bones, or teeth. More and more fossils have been found because paleontologists have been out searching for them.

The fossil record is the history of life that has been recorded by fossils. Paleontology is the science of discovering the fossil record. Darwin used fossils to formulate his theory of evolution. The fossil record is complete enough to show us that life has progressed from simple to complex. Unicellular prokaryotes are the first signs of life in the fossil record. These were followed by unicellular eukaryotes, then multicellular eukaryote. From these, fish evolved before plants and animals. Dinosaurs are directly linked to birds, but indirectly linked to mammals.

Transitional fossils have characteristics of two different groups. This helps tell us who is related to whom and how evolution occurred.

Archaeopteryx fossils are in between reptiles and birds. Whales have terrestrial ancestors. The origin of mammals has been well documented. The synapsids were mammal like reptiles. Their descendants were wolflike and bearlike predators along with piglike herbivores. The earliest true mammals were shrew size creatures.

Biogeography is the study of the distribution of plants and animals in different places throughout the world. This is consistent with the hypothesis that says that life forms evolved in particular places and then might have spread out. Islands have many unique species of animals and plants. This is because those plants and animals had no means of crossing the water to reach other lands.

Anatomical evidence is also used to help support evolution. Structures that are inherited from a common ancestor and are anatomically similar are called homologous. Analogous structures serve the same function, but do not share a common ancestry.

Almost all living organisms share the same biochemical molecules. Evolutionists have found many developmental genes shared in animals ranging from worms to humans.

The theory of evolution is scientific, and has been supported by scientific experiments and observations. Groups of people think that the teaching of ideas that run contrary to evolution should be taught in schools. This is Intelligent Design, or the thought that life could not have begun without the involvement of an intelligent agent.

Natural selection is a mechanism of adaptation discovered by Darwin. This is when a species becomes suited to its environment. The elements critical to the natural selection process include variation, competition for limited resources, and adaptation. Members of a species vary in physical ways which can be passed down generations. Even though each individual could produce many descendants, the number stays the same because resources are limited and competition for those resources results in unequal reproduction. Members of a population with advantageous traits are more likely to capture more of the resources and are more likely to reproduce, passing on their traits.

The binomial name of an organism gives its genus and species. The DNA coding for rRNA changes during evolution.

Primates are adapted to arboreal life, or living in trees. They have mobile limbs, grasping hands, a flattened face, binocular vision, a large complex brain, and a reduced reproductive rate. The order Primates has two suborders : prosimians and anthropoids. Prosimians include lemurs, tarsiers, and lorises. Anthropoids include monkeys, apes, and humans.

Primate limbs are mobile and hands and feet have five digits on each. Many primates have an opposable big toe and thumb. The opposable thumb makes it easy for a primate to reach out and bring food to the mouth. Binocular vision allows for depth perception. The brain is involved in controlling and processing information received from the hands and the thumb resulting in good eye hand coordination.

The human skeleton has many similarities to the chimpanzee skeleton. There are some differences however. The human spine exits from the center, and the ape spine exits from the rear of the skull. The human spine is S-shaped, while the ape spine has only a slight curve. The human pelvis is bowl shaped while the ape pelvis is longer and narrower. The human femurs angle inward, and ape femurs angle out. The human knee can also support more weight than an ape knee.

An evolutionary tree can be constructed once biologists have studied the characteristics of a group of organisms. Biologists have been unable to agree on which extinct form is the first hominid. Humans are on the hominid branch of the evolutionary tree. Lineage, or lines of descent, diverge from a common ancestor, the genes and proteins of the two lineages are almost identical. MAny genetic changes are neutral and these changes can be used as a molecular clock to indicate when the two groups diverged from each other. It is estimated that hominids split from the ape line of descent 7MYA.

One feature that is used to determine if a fossil is a hominid is bipedal posture, or walking on two feet. Two other important hominid features are the shape of the face and the size of the brain. Human features didn't evolve at the same rate.

The oldest hominid fossil was dated at 7 MYA. It was found in Chad and is called Sahelanthropus tchadensis. It was a skull that had smaller canines and thicker tooth enamel than an ape. Another fossil found 6MYA, orrorin tugenensis was found in eastern Africa and is also thought to be another early hominid.

The hominid line of descent really began with the australopithecines which evolved and diversified in Africa. Some were slender and some were robust. Their structures most likely related to their diets.

The first to be discovered was found in southern Africa in the 1920s by Raymond Dart. Dated 2.8 MYA, it was named Australopithecus africanus and was a gracile type. A robustus dated from 2 to 1.5 MYA and is also from southern Africa. Limb anatomy suggests that both of these walked upright. They also had fairly large brain sizes, making them a possible ancestral candidate for early Homo.

More than 20 years ago, nearly 250 fossils of a hominid called A. afatensis were unearthed.

most famous one, known as Lucy, was evidence to support standing upright and walking bipedally. Australopithecines were apelike above the waist and humanlike below the waist. This shows that humanlike characteristics did not all evolve at the same time. Mosaic evolution is when different body parts change at different rates and at different times.

Fossils are assigned to the genus Homo if the brain size is 600cm3 or greater, and if the jaw and teeth resemble those of humans, and if tool use is evident. Homo habilis may be ancestral to modern humans and is dated sometime between 2.0 and 1.9 MYA. Some of these fossils had brain sizes of 775 cm3. The cheek teeth were small, and it is likely that these members of the genus Homo were omnivores. Bones at their campsites show cut marks, meaning that tools were used to strip them of meat.

Culture has to do with human behavior and products and it depends upon the capacity to speak and transmit knowledge. Homo erectus fossils are found in Africa, Asia, and Europe. These are dated between 1.0 and 0.3 MYA. H. erectus had a larger brain and a flatter face than H. habilis. H. Erecturs was the first hominid to use fire.

The multiregional continuity hypothesis states that Homo sapiens evolved in several different locations. Opponents of this theory suggest the Out of Africa theory which says that H,. sapiens evolved only in Africa and then migrated to other areas.

Neandertals were dated about 200,000 years BP. The neandertal brain was slightly larger than H. sapiens. The Neandertals were culturally advanced. Many of them lived in caves, but some living in the open possibly built houses. They manufactured many different types of tools.

Cro-Magnons are the oldest fossils labeled as homo sapiens. They made advanced compound stone tools and may have been the first to throw spears. They are possibly the first to have a language. Their culture also included art and they sculpted figurines out of reindeer bones and antlers.

Humans have always been widely spread about the globe. Human variations are due to adaptations to local conditions. The differences between human populations are consistent with them having a common ancestor.

A biosphere is where organisms are found on our planet from the atmosphere to the depths of the oceans. The entire biosphere is a giant ecosystem. The ecosystem is a place where organisms interact among themselves and with the environment.

There are several distinctive major types of terrestrial ecosystems. These are called biomes. Temperature and rainfall are what define the biomes. Nonliving components of an ecosystem are called abiotic components. Living components are biotic. Some of the populations are autotrophs and some are heterotrophs. Autotrophs require inorganic nutrients and an outside energy source to provide organic nutrients for their own use. They are called producers because they produce food. Heterotrophs are consumers - they need a source of organic nutrients. Herbivores consume plants, carnivores consume meat, and omnivores feed on both. Detritus feeders feed on decomposing particles of organic matter.

A niche is the role of an organism in an ecosystem. This includes how it gets its food, what eats it, and how it interacts with other populations within its own community.

cannot exist without solar energy. Chemicals cycle when inorganic nutrients return to the producers. Only some of the organic nutrients made by autotrophs are passed on to heterotrophs. Only some of the nutrients taken in by heterotrophs are available to high level consumers. Metabolic wastes are excreted as urine. Wastes are nutrients made available to decomposers. Chemicals complete the cycle of an ecosystem when the inorganic chemicals become absorbed by producers from the atmosphere or the soil.

The paths of energy flow are represented by a food web that describes trophic, or feeding, relationships. Diagrams showing only one path of energy flow are known as food chains.

Only about ten percent of the energy of one trophic level is available to the next level. Energy losses result in pyramids. Pyramids of biomass eliminate size because biomass is the number of organisms multiplied by the weight of organic matter.

A biogeochemical cycle is the pathway by which chemicals circulate through ecosystems. They can be gaseous or sedimentary.

The water cycle begins with evaporation. This is when the sun causes freshwater to evaporate from the sea, leaving salt behind. Vaporized freshwater rises, condenses, and then falls as rain, snow, or another form of precipitation. Water can also evaporate from land and plants. Gravity returns all freshwater eventually to the sea. Runoff is water that flows into stream, lakes, wetlands, or the ocean. Humans interfere with the water cycle because they withdraw water from aquifers, they clear vegetation from land, and they interfere with natural purifying processes.

Carbon dioxide is the exchange pool for the carbon cycle. Organisms in both terrestrial and aquatic ecosystems exchange carbon dioxide with the atmosphere. Plants on land take it in from the air, and incorporate carbon into nutrients used by heterotrophs and autotrophs through the process of photosynthesis. When organisms respire, they return carbon to the atmosphere as carbon dioxide. Carbon dioxide from the air combines with water and produces bicarbonate ion which is a source of carbon for algae. The amount of bicarbonate in the water is equilibrium with the amount in the air. Living and dead organisms contain organic carbon. More carbon dioxide is being deposited in the atmosphere than is being removed. Carbon dioxide is being emitted due to human activities. This along with nitrous oxide and methane are known as greenhouse gasses because they allow solar radiation to pass through but don't really allow the escape of heat back into space. This contributes to global warming.

Nitrogen makes up 78% of the atmosphere. Plants do not make use of nitrogen, therefore it is a nutrient that can limit the amount of growth in an ecosystem. Nitrogen fixation occurs when nitrogen is converted to ammonium, which plants are able to use. Plants can also use nitrates as a form of nitrogen. The production of nitrates is called nitrification. Ammonium in the soil is converted to nitrate by soil bacteria. Nitrate producing bacteria convert nitrite to nitrate. During assimilation, plants take up ammonia and nitrate from the soil to produce proteins and nucleic acids. Denitrification is when nitrate is converted back into nitrogen gas. Human activities alter the transfer rates by producing fertilizers. Acid deposition occurs when nitrogen oxides and sulfur dioxide enter the atmosphere from the burning of fossil fuels.

During the phosphorus cycle, phosphorous trapped in the ocean moves onto land. On land the slow weathering of rocks places phosphate ions in the soil. Some of this becomes available to plants. Animals eat the producers and incorporate phosphate into teeth, bones, and shells. Death and decay of all organisms make phosphate ions available to producers again. human beings increase the supply of phosphate by mining. Overenrichment of waterways is called cultural eutrophication. Biological magnification is when a food change becomes more and more concentrated because the phosphate ions remain in the body and are not excreted. During the last 50 years, humans have polluted the seas to where many species are close to extinction.

Before the year 1750, the growth of the human population was slow. After that, as more reproducing humans were added, growth increased and the curve sloped steeply, indicating what is known as exponential growth. The growth rate of the population is determined by the difference between the number of people born each year and the number of people that die per year. In the wild, exponential growth means that a population is at biotic potential - the maximum growth rate under ideal conditions. The maximum population that the environment can support is called the carrying capacity.

The more developed countries have modest population growth, and the less developed countries show dramatic population growth. The LDCs experience such population momentum because they have a greater number of women entering reproductive years than older women leaving them. The three age groups of population are prereproductive, reproductive, and postreproductive. Most MDCs have stable age structure diagrams and their populations should remain the same if couples have fewer than two children.

A resource is anything from the biotic or abiotic environment that helps human beings meet their certain basic needs. Some resources are nonrenewable, meaning that they are limited in supply. These include amount of land, fossil fuels, and minerals. Renewable resources can be replenished naturally such as water. Pollution is an alteration of the environment in a negative way.

All humans need a place to live. There are more than 32 people for each square km of land worldwide. Forty percent of the population lives within 100 km of a coastline. Unfortunately, this leads to beach erosion and loss of habitat for marine organisms. Forty percent of the Earth's lands are deserts and land near it is in danger of becoming unable to support human life if humans don't manage it properly. Desertification is the conversion of semiarid land to desert conditions. Deforestation, or the removal of trees, allows humans to live where forests once stood. Unfortunately, this makes land subject to desertification.

Most freshwater is used by industry and agriculture. Seventy percent of all water is used to irrigate crops. In the MDCs, in domestic use, more water is used for bathing, flushing toilets, and watering lawns than is used for drinking and cooking. Dams are one way to replenish the supply of freshwater, but they have drawbacks as well. The salt left behind by evaporation increases salinity can make a river's water unusable downstream. Aquifers are reservoirs found just below the surface. This accumulates from rain that fell in far off regions. By 2025, two thirds of the world population may be living in countries facing serious water shortages.

Food comes from three activities : growing crops, raising animals, and fishing the seas. Some of the processes used to obtain these resources are harmful to the earth such as planting genetic varieties, heavy use of fertilizers and pesticides, generous irrigation, and excessive fuel consumption. Land used for farming is being degraded worldwide.

About 75% of the world's energy supply comes from fossil fuels, and 6% from nuclear power. Fossil fuels such as oil, natural gas, and coal come from the compressed remains of plants and animals that died many thousand years ago. Renewable types of energy include hydropower, geothermal, wind, and solar. Hydropower converts the energy of falling water into electricity. Geothermal energy happens when elements such as uranium, thorium, radium, and plutonium undergo radioactive decay below the Earth's surface and heat the surrounding rocks. Wind power is exactly what is sounds like. And solar energy is diffuse energy that must be collected, converted to another form, and stored.

Minerals are nonrenewable materials in the Earth's crust that can be mined. Some of them can be dangerous to human health such as lead, mercury, arsenic, and copper. The consumption of these minerals leads to hazardous wastes.

Biodiversity is the variety of life on earth. There are several factors that cause a loss of biodiversity, or extinction. Habitat loss, or the loss of habitable land, is one of the main causes. Alien species happen when humans introduce foreign species into new ecosystems and they take over the local species. Pollution issues such as acid deposition, global warming, ozone depletion, and synthetic organic chemicals also create a loss of biodiversity. Biodiversity is very positive and has many direct values to human well being such as medicinal, agricultural, and consumptive use values. There are also indirect values such as waste disposal, provision of freshwater, prevention of soil erosion, biogeochemical cycles, regulation of climate, and ecotourism.

A sustainable society is a society that would always be able to provide the same amount of foods and services as it does currently, at the same time preserving biodiversity.

Images are from these sites

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Embryonic/Fetal Development Lab

2008-12-02T18:50:00.000-08:00

10 Important Stages In Embryonic and Fetal Development

1. Implantation. This is when the zygote implants itself in the uterus and marks the beginning of the embryonic stage. This occurs sometime between day 6 and day 12.

zygote implanting in uterine wall

2. By the end of Week 6, the embryo is about half an inch in length and a heartbeat is sometimes audible through a vaginal ultrasound.

3. By the end of the 8th week, the embryo is the size of a bean. Bones are forming, and muscles can contract. Everything present in an adult human is also present in the embryo.

embryo at 8 weeks

4. Usually during week 14, the fetus gains the ability to suck. This is very important as this is the skill they will need as soon as they are born to gain their nutrients from their mother.

fetus at 14 weeks

5. By the end of week 16, fingerprints have developed. The fetus' movements may be felt as flutters by the mother.

6. By the end of Week 20, the embryo is about 8" long, and weighs about 12 ounces. Vernix, a white pasty substance protects the skin from amniotic fluid. The most exciting thing at this stage is that the heartbeat can usually be hear by a stethoscope placed on the abdomen.

7. One of my most exciting stages of pregnancy was after the 20th week, when the ultrasound is usually performed to check the baby's health and, if the mother wishes, determine gender.

My daughter's ultrasound during week 20 of my pregnancy

8. By the end of the 26th week, the baby could survive with medical technology if born at this time. Sleep and wake cycles have begun to develop. The fetus is about 14" long, and weighs about 2 1/4 pounds.

9. By the ends of the 36th week, the baby usually rotates to the head down position in preparation for birth.

10. Anytime during weeks 38-40 is considered full term. The baby is usually ready to be delivered. The average newborn is 19-21 inches long, and weighs 6 3/4 -10 pounds.

Images were used from these locations

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Unit 4 Section 1 Compendium Review

2008-11-23T12:14:00.000-08:00

I. Reproductive System

A. Human Life Cycle

1. Mitosis and Meiosis

B. Male Reproductive System

1. Orgasm in Males

2. Male Gonads

3. Hormonal Regulation

C. Female Reproductive System

1. Genital Tract

2. External Genitals

3. Orgasm in Females

D. Female Hormone Levels

1. Ovarian Cycle : Non Pregnant

2. Estrogen and Progesterone

3. Uterine Cycle :Non Pregnant

4. Fertilization and Pregnancy

E. Control of Reproduction

1. Birth Control Methods

2. Infertility

F. Sexually Transmitted Diseases

1. STDs caused by Viruses

2. STDs caused by Bacteria

II. Development and Aging

A. Fertilization

1. Steps of Fertilization

B. Pre-Embryonic and Embryonic Development

1. Processes of Development

2. Extraembryonic Membranes

3. Stages of Development

C. Fetal Development

1.Events

2. Development of Genitals

D. Pregnancy and Birth

1. Stages of Birth

E. Development after birth

1. Hypothesis of Aging

2. Effect of Age on Body Systems

The reproductive system is very different in males and females. Puberty is the series of events that brings about sexual maturity in humans. The reproductive organs have several different functions. First of all, the testes produce sperm in males, and the ovaries produce eggs in females. Males transport the sperm in ducts and females transport the eggs in the uterine tubes. The male penis delivers sperm to the female vagina. The uterus helps the fertilized egg to develop within a female. The testes and ovaries produce sex hormones that maintain the testes and ovaries and cause masculinization and feminization of several features.

Human DNA is distributed among 46 chromosomes inside the nucleus. Every cell in the human body has that number of chromosomes. When a cell divides by mitosis, or duplication division, the cell produces exact copies of itself. Human cells also can go through another process of division called meiosis, or reduction division. During meiosis, the number is reduced to 23, or the haploid number of chromosomes. Meiosis is the process by which sperm and egg cells are produced. Since the sperm cell has 23 chromosomes, as does the egg, when they combine they become a zygote and have the full 46 chromosomes.

The primary sexual organs, or gonads, are called testes which are within the scrotum. Sperm is produced by the testes and mature in the epididymis. Sperm has to reach maturation in order to swim to an egg. After leaving the epididymis, the sperm enter a vans deferens where they are stored. The vas deferens curve around the bladder and empty out into an ejaculatory duct which enters the urethra. During ejaculation, sperm exits the penis in a fluid called semen. Seminal fluid is made up of secretions from the seminal vesicles, the prostate gland, and the bulbourethral glands. Each individual component of semen appears to have its own function. Sperm are more viable in basic solutions which is what seminal fluid is. Swimming sperm require energy, which they get from fructose.

The male organ of sexual intercourse is called the penis. It has a long shaft and an enlarged tip. This tip is usually covered by a layer of skin called the foreskin, although some penises are circumcised (removal of foreskin). There is spongy erectile tissue that extends through the penis and contains distensible blood spaces. When a male is aroused, nerves release nitrous oxide which produces cGMP, causing the smooth muscle of incoming arterial walls to relax and the erectile tissue to fill with blood. This causes the penis to become erect. When sexual stimulation intensifies, sperm enters the urethra. Once the seminal fluid is in the urethra, ejaculation occurs which is caused by rhythmic muscle contractions. This is part of a male orgasm. After ejaculation, the penis returns to a flaccid state. There are up to 400 million sperm released during ejaculation.

The testes begin descending during the last two months of fetal development. They form inside the abdominal cavity, but descend down into the scrotal sacs. The scrotum helps to regulate the temperature of the testes by holding them closer to or further away from the body. A testis is composed of lobules which contain seminiferous tubules. This is where spermatogenesis, or production of sperm, occurs. It takes 74 days for sperm do develop from spermatogonia. Spermatozoa, or mature sperm, have three parts - the head, the middle piece, and the tail.

Androgens are the male sex hormones. They are secreted by cells between the seminiferous tubules. This is why they are called interstitial cells. The most important androgen is testosterone.

The hypothalamus secretes the hormone gonadotropin releasing hormone, which controls the testes' sexual function. There are two different GRHs - follicle stimulating hormone and luteinizing hormone. These are present in males and females. Testosterone brings about the male secondary sex characteristics that appear during puberty. Some of these characteristics are taller height, broader shoulders, and deeper voices. Testosterone is also what causes greater muscle development.

Ovaries are the female gonads. They lie on each side of the upper pelvic cavity and produce eggs, along with the female sex hormones estrogen and progesterone. The oviducts, which are more commonly known as the fallopian tubes, extend from the uterus to the ovaries. They end in fingerlike projections called fimbriae. When an egg bursts from the ovary, it is swept into an oviduct by both the fimbirae and the cilia that lines the oviducts. When the egg is in the oviduct is is propelled toward the uterus by muscle contraction and ciliary movement. Unless it is fertilized, and egg only lives 6-24 hours. When an egg is fertilized it becomes a zygote. In several days, a developing embryo arrives at the uterus and begins implantation. The uterus is the size and shape of an upside down pear. The oviducts join with the uterus at its upper end and the cervix is at its lower end and enters the vagina.

Development of the embryo and the fetus takes place in the uterus, or the womb. The endometrium is the lining of the uterus and participates in forming the placenta. There is a small opening in the cervix leading to the vaginal canal. The vagina acts as an exit for urine and menstrual flow and is the female sexual organ.

The vulva are the external female genitals. They include two large folds of skin called the labia majora. The labia minora are the two smaller folds. The vagina starts out with a ring of tissue called the hymen protecting it. The hymen is ruptured by sexual intercourse or other physical activities.

During stimulation, the labia minora, vaginal wall, and clitoris become engorged with blood. During this time the vagina expands and elongates. Mucus secreting glands provide lubrication for entry of the penis. At the height of stimulation, orgasm occurs.

Ovaries contain many follicles, each one containing an immature egg, or oocyte. Females are born with up to two million follicles, but by puberty that number has dropped to 3 0r 4 hundred thousand. Only about 400 follicles ever reach maturity. The ovarian cycle is when the follicle matures. It changes from a primary to a secondary to a vesicular follicle. Females usually only produce one egg per month. An oocyte undergoes meiosis I. The secondary oocyte undergoes meiosis II if it is fertilized by a sperm cell. When it is time, the vesicular follicle bursts, releasing the oocyte in a process called ovulation. The ovaries provide eggs and the sex hormones estrogen and progesterone. The hypothalamus has complete control of the sexual function of the ovaries through its secretion of GnRH.

Estrogen is responsible for body hair and fat distribution as well as other secondary sex characteristics. Also, the pelvic girdle is wider and deeper in females. The period in a woman's life during which this whole cycle ceases is called menopause. This usually occurs between the ages of 45 and 55. Estrogen and progesterone affect the endometrium which causes the uterus to undergo a 28 day series of events known as the uterine cycle. During the first 5 days, the hormone levels are low, causing the endometrium to disintegrate and the blood vessels to rupture. This is when menstruation occurs. During days 6-13, increased production of estrogen by a new ovarian follicle causes the endometrium to thicken. This is called the proliferative phase. On the 14th day, ovulation usually occurs. During the last half of the cycle, progesterone production increases and the endometrium triples in thickness preparing to receive a developing embryo.

After unprotected sexual intercourse, sperm will make there way into the oviduct. Once a sperm (only one) fertilizes the egg it becomes a zygote. This begins pregnancy. The placenta originates from maternal and fetal tissues. This is the region where exchange of molecules between maternal and fetal blood occurs. The placenta begins to produce human chorionic gonadotropin, or HCG. A pregnancy tests for this hormone. Then the placenta produces progesterone as well as some estrogen.

Birth control pills are taken to help prevent pregnancy from occurring. They are taken for 21 days and contain synthetic sex hormones. After that 7 days of inactive pills are taken. These hormones feed back and inhibit the hypothalamus and the anterior pituitary. They also thicken cervical mucus, preventing sperm from entering.

There are several means of birth control used to try to prevent pregnancy. Abstinence, or refraining from intercourse, is the only foolproof method. Contraceptives are medications and devices that reduce the risk of pregnancy. Oral contraceptives are pills. Another method is an intrauterine device which is a small piece of molded plastic that a physician inserts into the uterus. A diaphragm is a soft latex cup that lodges behind the pubic bone and fits over the cervix. Barrier methods include female and male condoms. Injections and vaccines are also available.

There are more permanent methods of contraceptives. Vasectomy consists of cutting and sealing the vas deferens so that sperm cannot reach the seminal fluid. Tubal ligation is when the oviducts are cut and sealed.

There is a new pill out called a morning after pill which is considered an emergency contraceptive. This contains synthetic progesterone which disrupts the uterine cycle and makes it difficult for an embryo to implant.

The failure of a couple to achieve pregnancy after regular, unprotected intercourse is called infertility. Approximately 15% of all couples are infertile. The most common cause of this is low sperm count in the male. A sedentary lifestyle is the most common cause of male infertility. Body weight is the most significant factor in female infertility.

There are many assisted reproductive technologies available for infertile couples today. Artificial insemination by donor is when sperm is placed in the vagina by a physician. Normally the sperm is from an anonymous donor. In vitro fertilization is when conception occurs in laboratory glassware. Immature eggs are retrieved by a needle and brought to maturity before concentrated sperm is added. After 2-4 days they are transferred to the uterus of the woman. Gamete intrafallopian transfer is when the egg and sperm are immediately placed in the oviducts after being brought together. In some instances, woman are paid by other women to have their babies. There is one last technology called intracytoplasmic sperm injection where a single sperm is injected directly into an egg.

There are several types of sexually transmitted diseases, or STDs. These are caused by viruses, bacteria, protists, fungi, and animals. There is effective treatment available for AIDS and genital herpes, which are caused by viruses. AIDS is the last stage of an HIV infection. There is no cure, but a treatment called highly active antiretroviral therapy is able to stop HIV reproduction to where it is not detectable in the blood. Human papillomaviruses are the cause of genital warts. Genital herpes is caused by herpes simplex virus. Symptoms can include tingling or itching sensation before blisters appear on the genitals. Hepatitis is an infection in the liver and can lead to death.

STDs that are caused by bacteria are curable with antibiotics. Chlamydia is usually mild in women. Men may feel a mild burning sensation during urination. Gonnorhea's symptoms include pain upon urination, and a thick greenish yellow discharge. It can also cause infertility in males. If a baby is exposed during birth, they may develop an eye infection leading to blindness. This is why all newborns are given eyedrops. Syphilis has three stages. During the primary stage, a chancre shows the site of the infection. The secondary stage is when the victim develops a rash and hair loss may occur. The tertiary stage lasts until death.

Sperm have a tail called a flagellum which allows it to swim. The plasma membrane of the egg is surrounded by the zona pellucida. The cells surrounding this area are called the corona radiata. During fertilization, several sperm attempt to penetrate the corona radiata. When a sperm head binds to the zona pellucida, digestive enzymes are released forging a pathway for the sperm. When the sperm binds to the egg, their plasma membranes fuse.

As a human being develops, four separate stages occur. The first stage is cleavage. Immediately after fertilization, the zygote divides creating multiple cells while not growing in size. The second stage is growth, in which the daughter cells begin to increase in size. Next is morphogenesis, or the shaping of the embryo. Differentiation is the stage when the cells take on a specific structure and function.

Extraembryonic membranes are not a part of the embryo. There are several functions of the extraembryonic membranes. The chorion develops into the fetal half of the placenta. The allantois extends away from the embryo and accumulates the urine produced by fetal kidneys. The yolk sac is the first of the embryonic membranes to appear. It contains food for the developing embryo. The amnion enlarges as the embryo enlarges, containing fluid for protection. The stages of development include fertilization through birth. Preembryonic development includes the first week. Following fertilization, the zygote repeatedly divides as it passes into the uterus. A blastocyst is a compact ball of embryonic cells. Each cell within the cell mass has the capability of becoming any type of tissue. Occasionally, the cells of the morula separate, forming twins.

Embryonic development encompasses the second week through the end of the second month of development. At the end of the first week, the embryo implants itself in the uterine wall. Occasionally, an embryo implants itself elsewhere, causing an ectopic pregnancy. This type of pregnancy is not successful. During the time of implantation, the chorion secretes enzymes that digest some of the tissue and blood vessels of the uterus. It also begins to secrete human chorionic gonadotropin. During this second week, the inner cell mass becomes the embryonic disk and the yolk sac and amniotic cavity form. During the major event of gastrulation, the inner cell mass becomes the embryonic disk. During the third week of development, the nervous system becomes the first organ system to be visually evident. A thickening appears along the entire length. The neural folds meet at the midline and the neural tube is formed. Development of the heart also begins this week. At four weeks, the embryo is only about a quarter of an inch in size. A body stalk connects the embryo to the chorion. The head and the tail lift up. The umbilical cord forms. Limb buds begin to appear and the head enlarges. The sense organs become visible. Between the sixth and eighth week of development, the embryo changes into a form recognizable as a human. The nervous system begins to develop reflex actions.

At the end of eight weeks the embryo is 1.5 inches long and weighs about the same as an aspirin tablet.

The placenta is where progesterone and estrogen are produced during pregnancy. They prevent any new follicles from maturing and they maintain the endometrium. The placenta's fetal side is contributed by the chorion and the maternal side consists of uterine tissues. The umbilical cord contains the umbilical arteries and vein. The arteries carry oxygen poor blood to the placenta. The vein carries blood that is rich in nutrients and oxygen away from the placenta to the fetus.

The third through ninth months of development are known as fetal development. Head growth begins to slow down during the third month. Fingernails, nipples, eyelashes, eyebrows, and hair appear. Cartilage is slowly replaced by bone. Sometime during the third month males are distinguishable from females.

During the fourth month, the fetal heartbeat can be heard by placing a stethoscope on the mother's abdomen. At the end of this month the fetus is about 6 inches long and weighs about 6 ounces.

The mother begins to feel movement sometime during the fifth and seventh months. During this time the wrinkled skin is covered by a fine down called lanugo which is coated with a white, cheeselike substance called vernix caseosa.

The eyelids are open during this time. At the end of the seventh month, the fetus is about 12 inches long and weighs about 3 pounds. If the fetus was born now, it is possible to survive.

At the end of nine months the fetus is about 20.5 inches long and weighs about 7.5 pounds. The fetus usually rotates during the end of development so that its head is pointed toward the cervix to prepare for birth. If the fetus does not turn and is rump down, a breech birth is likely to occur. This makes it difficult for the cervix to expand and a cesarean section may be how the baby needs to be delivered.

The sex of a person is determined as soon as fertilization occurs. Males have XY chromosomes and females have XX chromosomes. It is impossible to tell just by inspection whether an unborn child is a boy or a girl during the first several weeks of development. Gonads begin developing during the seventh week. At 14 weeks, the primitive testes and ovaries are located deep inside the abdominal cavity. At fourteen weeks the urogenital groove has disappeared in males and the scrotum forms. In females, the groove persists and becomes the opening for the vagina.

The absence of one or more of the sex hormones causes ambiguous sex determination. In this case, the person has the external appearance of a female but the gonads are absent. In androgen insensitivity syndrome, the individual develops as a female because the receptors for testosterone are ineffective and the external genitalia develop as a female. However, the individual has testes inside the body.

When a woman first becomes pregnant, she may experience nausea and vomiting, loss of appetite, and fatigue. These symptoms usually subside and the mother has a period of increased energy levels. Weight gain is caused due to breast and uterine enlargement, weight of the fetus, amniotic fluid, the size of the placenta, and other factors. The increased weight can cause lower back pain.

myself at 7 months pregnant

The arteries in the uterus expand and this leads to low blood pressure. An increase in the number of red blood cells follows and cardiac output increases by 20-30%. The uterus ends up occupying most of the abdominal cavity. Compression of the ureters and urinary bladder can result in stress incontinence. Compression of the inferior vena cava can result in edema and varicose veins. Stretch marks, or striae gravidarum typically appear over the abdomen and lower breasts as a result of stretching of the skin.

Throughout pregnancy, the uterus has contractions. Near the end of pregnancy, contractions become stronger and more frequent. False labor contractions are called Braxton Hicks contractions. The onset of true labor is contractions that occur regularly every 15-20 minutes and last for at least 40 seconds. Parturition is the process of giving birth to an offspring. Prior to the first stage, there can be what is known as a "bloody show" which is caused by the expulsion of a mucous plug from the cervical canal.

During the first stage of labor, the uterine contractions occur and the cervical canal slowly disappears. The lower part of the uterus is pulled toward the baby's head. This is called effacement. If the amniotic membrane has not ruptured, it may do so during this phase. Stage one ends when the cervix is completely dilated.

During stage 2, the uterine contractions occur every 1-2 minutes and last for about a minute. This is accompanied by a desire to push. As the baby's head descends it turns so that the back of the head is uppermost. An episiotomy is sometimes performed to enlarge the vaginal orifice. Once the head is delivered, the physician holds the head and guides it downward until the rest of the baby is out. Once the baby is breathing normally the umbilical cord is cut.

The third stage is when the placenta, called the afterbirth is delivered.

Development does not end at birth. It continues throughout our lives during infancy, childhood, adolescence, and adulthood. Aging is the progressive changes that contribute to an increased risk of infirmity, disease, and death. Gerontology is the study of aging. The number of people over the age of 65 will increase 147% in the next half of a century. The human life span is a maximum of 120-125 years.

There are three hypotheses of aging. Several researchers believe that aging has a strong genetic basis. They have worked with roundworms and found many genes whose expression decreases life span. Another theory contains a whole body process; This is due to a decline in the hormonal system which affects many organs of the body. Some of the diseases and problems seen in older humans include diabetes type 2, menopause, and many other things. The immune system does not perform as well as a person gets older. Extrinsic factors are another theory for aging. This states basically that how we take care of ourselves affects how well our bodies will function as we get older.

Age effects many different body systems in many ways. Skin becomes thinner and less elastic. This loss of thickness causes some of the sagging and wrinkling of the skin. There are fewer sweat glands making homeostatic adjustment to heat limited. Oil glands are also fewer, causing skin to crack.

The leading cause of death today is cardiovascular disorders. The heart begins to shrink during aging. Blood flow to the liver is reduced, and the liver does not metabolize drugs very efficiently. Blood supply is also reduced to the kidneys. The digestive tract begins to lose tone, and there is a reduction of saliva and gastric juice. However, few neural cells of the cerebral cortex are lost. Cognitive skills remain unchanged. Reaction time slows. Loss of skeletal mass is common, but can be controlled by exercise. Females undergo menopause. Males undergo andropause. Females on average live longer than males.

Aging is inevitable, but by developing health habits now, we can prepare for successful old age.

4 generations - ages 2 through 85

Images are from these sites:

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Evaluation Unit 3

2008-11-15T19:05:00.000-08:00

Self

1. 3 Aspects I am proudest of...I am proud of the compendium reviews I did for this unit - I think they have everything they needed, I am proud of the fact that I was able to involve my daughter once again in the major project, and I am proud of the fact that I managed to get everything done with so little time to do my homework.

2. 2 aspects that could improve...I am still learning my husband's new computer and had a hard time adding pictures to my posts, I also wish I had more time to have worked on the model of the joint

3. I think my overall grade for this unit should be a B

4. I think I can do better next time by starting the big project earlier, in case we have more illnesses or whatever that set me back.

Unit

1. I was most engaged in the chapter on muscles...I thought it was very interesting.

2. I was most distanced during the first lab with the leeches...my husband's new computer was not doing what I wanted it to do, so it prevented me from enjoying my lab

Ethics Essay Unit 3

2008-11-15T13:21:00.001-08:00

Exercise...we all know it is good for us, so why don't enough of us do it? There is a myriad of excuses for why people don't exercise as much as they should. There aren't really two sides to this issue since we all KNOW that exercise is a good thing. Unfortunately, many of us, have excuses of why we don't do it. There are so many benefits to exercise...it decreases the risk of cancer, helps us feel good physically and mentally, helps improve our health and fitness. A lot of people simply don't like the inconvenience of exercise. They don't want to get up earlier to walk to work instead of driving, or they are too tired after work to go for a walk.

I know I don't exercise quite as much as I should, but I do try to fit it in. My family and I live a block from Walgreens, and 2 blocks from Walmart. As long as we are not making big purchases, we walk to those locations.

I make sure my daughter is active as much as possible - her weekly schedule includes a Thursday morning music and movement class, a Saturday morning gymnastics class, and Sunday morning swim time. She is a bundle of energy, and it doesn't take much to motivate her to get up and get moving. My husband enjoys riding his mountain bike to and from school when the weather's not terribly cold. I work in an enviroment where we do a lot of walking and physical activity throughout the day.

There are days when I don't feel like doing anything after getting home from work, and days that I give in and just sit down. Although, since having a child 2 years ago, the time to just sit down has decreased to nil. We all owe it to ourselves to make that time to exercise, no matter how worn out we feel. In the long run, it will help us to be more energetic, healthy people to a much older age in our life.

Cartoon from this site:29_couch_potato_watching_tv_and_eating_donuts.png

Major Lab Unit 3

2008-11-15T12:33:00.000-08:00

I choose to do a model of the arm with the elbow joint illustrated. The elbow is able to move because muscle fibers are stimulated which makes them contract by motor neurons. The axons of the neurons are in the nerves. When the nerve impulses reach an axon, ACh is released which binds to receptors in the sarcolemma. The sarcolemma creates impulses that spread down T tubules to the sarcoplasmic reticulum. This whole process creates movement, enabling a joint to move.

My daughter helped me with this assignment by helping to make the homemade playdough that was used.

Raziel adding the flour for the dough

stirring the dough

kneading food color into the dough

muscle fiber model

calcium in a muscle contraction

model of elbow joint in the arm

closeup of the elbow joint

Here are what were used for the parts :

homemade playdough - bones, muscles, tendons

uncooked spaghetti noodles- myofibrils

Jujubes candy - nucleus

thread of different colors - T tubule, sarcoplasmic reticulum, tropomyosin

Skittles and Jubues - actin filaments, troponin and Ca2+

packing tape - sarcolemma

Muscle Lab

2008-11-15T12:24:00.000-08:00

This lab was to determine the effects of temperature and fatigue on muscle action. It was interesting to see how fast a muscle wore down. The first thing I did was to feel muscles that had contracted.

1. The three changes I observed in a muscle while it was contracted was that it tightened, felt firmer, and was shorter in length.

Then I timed myself to see how many tight fists I could make in 20 seconds. I was able to make 15. After soaking my hand in ice water for a minute, that number went down to 12.

2. The cold temperature of the water caused my muscles in my hand to contract slower. The muscles were slower to respond in making a fist.

The next part of my experiment involved fatigue. I repeatedly counted how many times I could make a fist in 20 seconds. I did this trial 10 times with no breaks in between. My husband wanted to attempt this also. Here is the graph

4. Fatigue made it a lot harder for the muscles to work. It also caused muscle pain. The number of times I was able to squeeze the ball steadily decreased. My husband's decreased, then went up because he was forcing himself to try for opposite results, and then went steadily down again, leaving him sorer than I was.

In conclusion, both temperature and fatigue can slow down muscle function.

Chapter 11 and 12 Compendium Review

2008-11-09T13:54:00.000-08:00

I. Skeletal System

A. Overview

1. Functions

2. Anatomy of a Long Bone

B. Bone Growth, Remodeling, and Repair

C. Bones of the Axial Skeleton

1. The Skull

2. The Hyoid Bone

3. The Vertebral Column

4. The Rib Cage

D. Bones of the Appendicular Skeleton

E. Articulations

II. Muscular System

A. Overview

1. Types of muscles

2. Functions

3. Skeletal muscles of the body

B. Skeletal muscle fiber contraction

1. Muscle fibers

2. Control of contraction

C. Whole muscle contraction

1. motor units

2. energy

3. fast twitch and slow twitch

D. Muscular Disorders

E. Homeostasis

Bones, cartilage, and fibrous connective tissue are all components of the skeletal system. The skeleton plays many important roles in the body. It supports the body, protects soft body parts, produces blood cells, stores minerals and fat, and permits flexible body movement in conjunction with the muscles.

The main portion of a long bone, or shaft, is called the diaphysis. Inside is a large medullary cavity, composed of compact bone. Compact bone is very highly organized and contains osteons, which are tubular units. Spongy bone is very unorganized in appearance. Cartilage is more flexible than bone, but not as strong. It is made up of cells called chondrocytes. There are three types of cartilage : hyaline, fibrocartilage, and elastic cartilage. Fibrous connective tissue contains cells called fibroblasts and makes up ligaments and tendons.

There are several different types of cells that are involved in growth, remodeling, and repair of bones. Osteoblasts are bone forming cells that promote sending calcium salts into the matrix. Osteocytes come from osteoblasts and maintain bone structure. Osteoclasts absorb bone cells. They break down bones.

The formation of a bone is called ossification. In a process called intramembranous ossification, bones develop in between the sheets of fibrous connective tissue. The most common type of ossification is endochondral ossification. During this process, bone replaces cartilaginous models of the bones gradually. Chondrocytes put down hyaline cartilage. As the cartilage model calcifies, the chondrocytes disappear. Osteocytes secrete bone matrix which undergoes calcification. This forms a bone collar, which covers the diaphysis. Blood vessels lay down spongy bone. The spongy bone is absorbed by osteoclasts and becomes the medullary cavity. A band of cartilage called a growth plate is in between the primary center and all secondary centers. Once the growth plates close, growth in bone length no longer occurs.

Hormones, which are chemical messengers, are involved in bone growth. Vitamin D is converted to a hormone that helps with the intestinal absorption of calcium. When calcium can't be absorbed, children can develop a condition called rickets. Growth hormone stimulates growth of the growth plates.

Bone renewal, also known as remodelling, is when bones break down and reform. Up to 18% of the bones in our body are recycled every year. Bone recycling helps the body regulate how much calcium is in the blood.

Bone repair happens after a bone breaks or fractures. There are four steps of repairal. First, blood escapes and forms a hematoma between the broken bones. Then, a fibrocartilaginous callus fills the space between the ends of broken bone. Next, a bony callus joins the bones together. Finally, bone remodelling takes place.

The axial skeleton is in the midline of the body. Its main components are the skull, the hyoid bone, the vertebral column, and the rib cage. The cranium and the facial bones make up the skull. The cranium is made up of eight bones that fit tightly together. It protects our brain. Some of the bones in the cranium contain the sinuses. The major bones of the cranium share the names of the lobes of the brain. The facial bones are what give our faces structure. The most noticeable of these are the mandible, the maxillae, the zygomatic, and the nasal bones. The hyoid bone is attached to the temporal bones and the larynx. It anchors the tongue and is where the muscles associated with swallowing attach. There are 33 vertebrae in the vertebral column. The vertebral column protects our spinal cord. In between the vertebrae are intervertebral disks, made up of fibrocartilage which serve the purpose of padding. The rib cage is also known as the thoracic cage and consists of the ribs and the sternum. It protects internal organs, yet is flexible. There are twelve pairs of ribs in the rib cage. The sternum protects the heart and the lungs.

The bones within the pectoral and pelvic girdles and their attached limbs make up the appendicular skeleton. There are two pectoral girdles in the body. Each has a scapula and a clavicle. These are the shoulder blade and the collarbone. The humerus comes off the scapula and the radius and ulna come off the humerus. The hand has many bones, causing it to be capable of great flexibility. The pelvic girdle is where our pelvis is. Our legs descend from this, containing the femur, and the tibia and fibula. The foot, like the hand, has many bones for flexibility.

Bones are jointed. These joints are either fibrous, cartilaginous, or synovial. Most fibrous joints are immovable. Cartilaginous joints are only slightly movable. Synovial joints permit free movement.

There are three types of muscle tissue in humans : smooth, cardiac, and skeletal. They all have cells called muscle fibers. Smooth muscle cells are spindle shaped and usually form sheets. Smooth muscle does not fatigue easily. Cardiac muscle is what goes around the heart and forms the heart wall.

Skeletal muscles have many functions. They support the body, make bones move, help maintain constant body temperature, assist movement in cardiovascular and lymphatic muscles, and help protect internal organs and stabilize joints. Skeletal muscles operate in pairs. The beginning of a muscle is on a stationary bone and the insertion is on a bone that moves.

muscles shorten when they contract.

Special names have been assigned to some of the components in a muscle fiber. The sarcolemma, sarcoplasm, and sarcoplasmic reticulum are the same as a plasma membrane, cytoplasm, and endoplasmic reticulum in any other cell. The sarcolemma forms T tubules that penetrate the cell and come into contact with parts of the sarcoplasmic reticulum. The sarcoplasmic reticulum encases thousands of myofibrils. Skeletal muscles have both light and dark bands. These bands are called striations. The thick bands are made up of myosin and the thin ones are made up of actin.

When the muscles are stimulated, calcium is released. The movement of actin filaments relating to myosin filaments is known as the sliding filament model. The entire region containing axons is known as the neuromuscular junction. There are two other types of proteins in an actin filament. These proteins are tropomyosin and troponin.

A nerve fiber combined with the muscle fibers that it innervates is a motor unit. All of the muscles in a motor unit contract at the same time. Maximal sustained contraction is called tetanus. It is desirable to have good muscle tone, with the muscle being firm and solid.

Muscles have four possible energy sources. These are muscle triglycerides, plasma fatty acids, blood glucose, and muscle glycogen. Muscle cells also store ATP which is needed for contraction. The CP pathway is the fastest way for muscles to produce ATP. Fermentation can produce two ATPs when glucose is broken down. Cellular respiration is another way that muscle cells can acquire more ATP.

Fast twitch muscle fibers are designed for strength and are usually anaerobic. Slow twitch fibers are steadier and more enduring. Delayed onset muscle soreness is muscles contracting while they are lengthening, and appears 24-48 hours after strenuous exercise.

Common muscular conditions are spasms, convulsions, cramps, facial tics, sprains, and strains. Tendinitis is when the gliding motion of a tendon is impaired and the tendon is inflamed. Bursitis is inflammation of a bursa (a sac filled with a smooth, slippery surface that helps muscles and tendons glide).

Muscular diseases can be more serious. Myalgia is chronic aching muscles. Muscular Dystrophy is characterized by progressive degeneration of muscles. Myasthenia gravis is an autoimmune disease affecting the muscles of the face, neck, and extremities. Lou Gehrig's disease, or ALS, is characterized by the gradual loss of certain abilities.

The skeletal and muscular systems work together to produce movement and to protect body parts. Bones store and release calcium and blood cells are produced in red bone marrow. Muscles help to maintain the temperature of the body by constricting or contracting.

I used images from the following sites

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Compendium Review Chapters 13 & 14

2008-11-08T11:43:00.001-08:00

I. The nervous system

A. Overview

1. nerve tissue

2. neuron structure

3. myelin sheath

4. nerve impulse

5. action potential

6. synapse

B. Central Nervous System

1. spinal cord

2. brain

C Limbic System and higher mental functions

D. Peripheral Nervous System

1. somatic system

2. autonomic system

E. Drug Abuse

II. Senses

A. Sensory Receptors and Sensations

1. types of receptors

2. how sensation happens

B. proprioceptors and cutaneous receptors

C. Senses of Taste and Smell

D. Sense of Vision

E. Sense of Hearing

F. Sense of Equilibrium

The nervous system is divided into two major sections : the central nervous system, or CNS, and the peripheral nervous system, or PNS. The CNS consists of the brain and spinal cord, and the PNS consists of nerves. There are three specific functions of the nervous system :receive sensory input, perform integration, and generates motor output.

There are two types of cells found in nervous tissue. Neurons transmit nerve impulses in the nervous system, and neuroglia support and nourish the neurons. There are three specific types of neurons : a sensory neuron takes nerve impulses to the CNS, motor neurons take nerve impulses away from the CNS, and effectors carry out our responses to environmental changes. All neurons have three parts, a cell body, dendrites, and an axon.

A protective layer called a myelin sheath covers many axons. In the PNS this covering is formed by Schwann cells. The gaps in an axon where there is no myelin sheath are called nodes of Ranvier. Long axons are more likely to have a myelin sheath. The myelin sheath helps with nerve regeneration in the PNS.

Nerve impulses pass along information in the nervous system. A voltmeter measures voltage and helps us to study the nerve impulse. When the axon is not conducting any impulses, the voltmeter registers membrane potential of about 65mV.

An action potential is a rapid change in polarity across an axonal membrane during a nerve impulse. It requires two types of gated channel proteins : sodium and potassium.

When there is no myelination on an axon, the action potential at one location causes an adjacent part to produce an action potential. When an impulse has passed by each portion of an axon, a refractory period occurs and the sodium gates will not open, ensuring that the action potential does not move backwards.

All axons branch into many fine endings tipped by an axon terminal which is very close to the dendrite or cell body of another neuron. This area of close proximity is known as a synapse. Transmission across a synapse is carried out by neurotransmitters. There are more than 100 substances known to be neurotransmitters. A single neuron is on the receiving end of many signals. They integrate these signals, summing up excitatory and inhibitory signals. Excitatory signals cause an axon to transmit a nerve impulse, an inhibitory prohibits the axon from doing so.

The CNS is made up of the spinal cord and the brain. Both of these are protected by bone. They are also wrapped in protective membranes known as meninges. The CNS is composed of gray matter which contains cell bodies and nonmyelinated fibers, and white matter which contains myelinated axons that run together in tracts.

The spinal cord begins at the base of the brain and extends into the vertebral canal. The spinal nerves project from the cord i between the vertebrae. The central canal contains cerebrospinal fluid. The spinal cord is the means of communication between the brain and peripheral nerves. The center for thousands of reflex arcs is in the spinal cord.

The cerebrum is the largest portion of the brain. It is the last center that receives sensory input and carries out integration. It coordinates activities of all other parts of the brain. The cerebrum has two halves, called cerebral hemispheres. Each hemisphere is divided into lobes - the frontal lobe, parietal lobe, occipital lobe, and temporal lobe. Each lobe is associated with different functions. The cerebral cortex is a layer of gray matter that covers the cerebral hemispheres. The primary motor area is located in the frontal lobe. The primary somatosensory area is in the parietal lobe. This is where sensory information from the skin and skeletal muscles arrives. Integration occurs in places called association areas. Processing centers receive information from other association areas. The prefrontal area uses this information to reason and plan actions. The ability to speak is dependent on two areas called Wernicke’s area and Broca’s area.

The cerebellum is under the occipital lobe of the cerebrum. It receives sensory input from the eyes, ears, joints, and muscles. The brainstem contains the midbrain and the medulla oblongata which regulates heartbeat, breathing, and blood pressure. The reticular formation is a main component of the reticular activating system which arouses the cerebrum and causes a person to become alert.

The limbic system is what controls our emotions and higher mental functions. This system is located deep in the cerebrum. The amygdala can cause experiences to have emotions associated with them and creates fear. The hippocampus is important to learning and memory.

Memory is defined as the ability to hold a thought in mind. Learning is the ability to retain and utilize past memories. There are several different types of memory :

short term, long term, semantic (letters. numbers, words) and episodic(persons and events).

There is another type of memory called skill memory which is involved in performing motor activities as we learn them. Language comes from semantic memory.

The left and right hemispheres of the brain serve different functions. The left half is associated with verbal, logical, and rational thoughts. The right is associated with nonverbal, intuitive, and creative thoughts.

The peripheral nervous system, or PNS, is where our nerves are. Humans have a dozen pairs of cranial nerves that are attached to the brain. There are 31 pairs of spinal nerves which emerge from the spinal cord. A dorsal root ganglion is the cell body of a sensory neuron.

The somatic system is part of the PNS. It serves the skin, skeletal muscles, and tendons. These nerves take sensory information from external receptors to the CNS and motor commands to the skeletal muscles.

The autonomic system is another part of the PNS. Its function is to regulate the activity of cardiac and smooth muscles and glands. It is divided into two areas. The sympathetic division kicks in in emergency situations, accelerating the heartbeat and dilating the bronchi. The parasympathetic division promotes all of the internal responses coming from a relaxed state.

Drugs can affect the nervous system and alter the mood or emotional state. Drug abusers take drugs that affect the reward circuit to where they neglect their basic needs and continue drug use. Drug abuse becomes obvious when a person is taking a drug at a dose level and under circumstances that can increase the risk of a harmful effect.

Alcohol is the most accepted form of drug use. It can have harmful effects on the brain and the body. It very easily crosses the blood brain barrier and causes damage to several tissues, including the liver and the brain.

Nicotine is another common form of drug use. It binds to neurons in the CNS, releasing dopamine.

While alcohol and nicotine are legal, there are other illegal drugs that are used and cause severe problems in the nervous system. Some of the more well known ones are cocaine, methamphetamine, heroin, and marijuana.

There are four categories of sensory receptors in humans. The first type is a chemoreceptor. These respond to chemical substances in the immediate area. Pain receptors are a type of chemoreceptors and are naked dendrites that alert us to possible danger. Photoreceptors respond to light energy and provide us with the sense of vision. Mechanoreceptors are stimulated by mechanical forces and result in pressure, giving us the sense of touch. Thermoreceptors are stimulated by changes in temperature.

Sensory receptors generate nerve impulses. When these impulses arrive at the brain, sensation occurs.

Proprioceptors, cutaneous receptors, and pain receptors send nerve impulses to the spinal cord where they travel to the somatosensory areas of the cerebral cortex. Proprioceptors are involved in reflex actions maintaining the body’s equilibrium and posture. They help us to be aware of the position of our limbs in space. Cutaneous receptors are located in the dermis of the skin and make the skin receptive to touch, pressure, pain, and temperature.

The senses of taste and smell are called chemical senses. Taste cells and olfactory cells contain chemoreceptors. Adult humans have about 3,000 taste buds on their tongue. There are four primary types of taste - sweet, sour, salty, and bitter. Taste buds have an opening called a taste pore. Molecules bind to the receptor proteins and generate nerve impulses that go to the brain. When the reach the gustatory, or taste, cortex, they are interpreted as tastes.

About 80-90% of what we taste is related to smell. Our sense of smell comes from 10-20 million olfactory cells located high in the roof of the nasal cavity. Each olfactory cell has only one type of receptor proteins. Different odors stimulate different olfactory cells.

Our senses of vision requires the eyes and the brain. The eyeball has three layers - the sclera, the choroid, and the retina. The lens is located in the choroid layer, and its function is to focus images on the retina. The lens and the humors assist in this. Rays of light pass through the lens and light rays are refracted when brought into focus. The photoreceptor have two structures - rod cells and cone cells. The retina has three layers of neurons. The rod cells and cone cells synapse with the bipolar cells which synapse with ganglion cells and the axons become the optic nerve. There are no rods and cones where the optic nerve exits the retina. This produces a blind spot in each eye. In order to reach the visual cortex, optic nerves carry impulses to the optic chiasma. This is where depth perception comes from. Some people have distance problems with their eyes. Nearsighted people have an elongated eyeball causing them to see close objects better than those at a distance. Farsighted people have shortened eyeballs which cause the opposite vision. Color blindness is another common abnormality of the eye.

The ear is where we get our sense of hearing. The ear consists of the outer, middle, and inner sections. The outer ear consists of the pinna and the auditory canal. The middle ear begins at the tympanic membrane (eardrum), and ends at a bony wall containing the oval window and the round window. The inner ear is filled with fluid. Hearing begins when sound waves enter the auditory canal. These sound waves vibrate molecules. The stapes strikes the oval window's outer membrane, causing it to vibrate, which passes pressure to the fluid in the cochlea. The sense organ for hearing is called the spinal organ which is located in the cochlear canal. Each part of this organ is sensitive to different wave frequencies.

The sense of equilibrium also comes from our ears. Mechanoreceptors in the semicircular canals detect rotational and angular movement of the head, known as rotational equilibrium. The base of the canals are called the ampulla. The brain uses information from the hair cells in the ampulla to maintain equilibrium through motor output to skeletal muscles that can right our position in space. The mechanoreceptors in the utricle and saccule detect movement of the head in the vertical or horizontal, known as gravitational equilibrium.

Images were from these sites

http://academic.wsc.edu/faculty/jatodd1/ap1/muscle.jpg, http://cwx.prenhall.com/bookbind/pubbooks/morris5/medialib/images/F02_01.jp

ghttp://www.faqs.org/health/images/uchr_02_img0126.jpg

http://www.dwp.gov.uk/medical/med_conditions/images/brain.gif

MPj03210900000[1].jpg

nature05401-f1.2.jpg

eye.jpg ear.gif

Leech neuron lab write up

2008-11-08T11:29:00.001-08:00

photo 1 - manipulator with oscilloscope trace

photo 2 - ultraviolet image of neuron with dye showing shape

The electrode is measuring the effect of different stimulus on the neurons.

Leeches are used for these experiments because their nerve cords are very large, and the neurons are easily accessible. A sensory neuron transmits impulses to the CNS after a sensory receptor has been stimulated. A motor neuron conducts nerve impulses away from the CNS and innervates muscles and glands. I thought it was very interesting the way some cells responded to certain stimulus while not responding to others at all.

Unit 2 Self Evaluation

2008-11-06T19:35:00.000-08:00

1. Three three aspects that I was proudest of myself in this unit were first of all, my ability to get it all done early so I could enjoy my family vacation, my big lab project where I included my husband and daughter, and the fact that I am able to understand the material where science has always been difficult for me.

2. The two aspects that need improvement are that I wish I had more time to spend on homework, and I think I kind of rushed my compendium reviews this time around.

3. I think my overall grade for this unit should be a B

4. It could have gone better if I wasn't trying to juggle a full time job, full time taking care of the house, and full time care of a 2 year old (my husband is a nursing student and spends all his time studying or in class so I am pretty much on my own 24/7), and trying to accomplish a class. But, I will continue doing my best in this class and hopefully one day soon, will have more time to devote myself more fully to my studies.

1. I was most engaged in this unit with the whole lab on pulse, respiration rate, and blood pressure. It was fun to let my daughter be included and it was interesting to watch the way those measurements changed.

2. I don't think I ever felt distanced during this unit.

3. I appreciate Professor Frolich's quick responses to questions during the unit.

4. I didn't find any action puzzling during this unit.

5. I was surprised at how much fun I had with this unit

Major Lab Unit 2

2008-10-09T20:29:00.000-07:00

The purspose of this lab was to see the effect that different activities have on our body's respiratory system. There were four elements measured : pulse rate, respiratory rate, systolic blood pressure, and diastolic blood pressure. After taking all of those measurements five different times after taking a 20 minute rest (difficult to acheive with a 2 year old pouring a plastic cup of Smarties down my shirt), I chose three activities to test their affect on my body. I choose a subdued activity, reading to and snuggling with my daughter; a high energy activity, dancing to The Wiggles with my daughter; and a regular activity, eating dinner. Each of these activities was repeated and measured three times and the average measurement calculated.

I couldn't get the table to copy, so here is my hypothesis as to what will happen to my rates after each of the activities in comparison to my resting rate.

Reading to my daughter : I predict that all four measurements will be lower

Dancing with my daughter : I predict that all four measurements will be higher

Eating dinner : I predict that all four measurements will be very similar to my resting rates.

taking my resting pulse rate (I wasn't lying about my daughter pouring a cup of smarties down my shirt)

taking my resting respiration rate

taking my resting blood pressure

snuggling and reading with my daughter

dancing to The Wiggles with my daughter

eating dinner

The results are as follows in the bar graphs:

My hypothesis proved to be correct for the most part. My pulse rate decreased significantly while reading, was suprisingly similar to my resting rate while dancing, and was lower while eating. My respiratory rate decreased significantly whild reading, increased significantly while dancing, and was very similar to my resting rate while eating. My systolic blood pressure decreased while reading, increased quite a bit while dancing, and slightly increased while eating. My diastolic blood pressure decreased while reading, increased while dancing, and decreased while eating.

I think my eating hypothesis was thrown off a bit because I wasn't that relaxed at dinner...I was tired from work, my husband was doing homework, and I was running late trying to get dinner ready by myself. Other than that, there were no problems - I wore myself out dancing to The Wiggles, but my daughter thoroughly enjoyed helping Mommy with homework.

In conclusion, everything we do effects our circulatory and respiratory systems, even if in just the smallest way. I think that the rate of our breathing is most susceptible to the differences.

Ethical Essay Unit 2

2008-10-07T20:40:00.000-07:00

Ethical Essay Unit 2

I.Introduction – America’s problem with eating
II. Fast Food/ convenience food
III. Eating healthy
IV. My viewpoint
V.What’s in store

Today’s society is all hustle and bustle. The economy is such that housewives are almost a thing of the past, as both parents struggle to earn a living to support their families. With housewives being few and far between, who’s at home to prepare a healthy, well balanced dinner for the family? When mom (or dad) gets home, they are both usually tired, and no one is in the mood to take the time to prepare a balanced meal. While intentions might be good, often it is the easy to prepare, or heat and eat foods that are reached for. In the cases where families can afford it, fast food is the answer to this crunch for time. It’s already prepared, no one has to bother with it, what’s the big deal, right? But it is becoming a big deal as America’s, (and the World in general) obesity problem rises and cases of heart disease is on the increase. The fast food franchises are always showing commercials, enticing us with their mouthwatering burgers, and “value” meal prices. Marketers are always advertising the newest snack food and the newest desserts. How many commercials do you see trying to promote fruits, vegetables, and the like? A few, maybe, but nowhere near the alternative.
Many people try to justify their diet of fast food or convenience food by saying that they are just too busy to take the time to fix anything healthy. It’s so much easier to grab a quick snack that’s right by the checkout stand (hmmm…that display usually includes beef sticks, chips, and candy bars) than to walk all the way into the store to find a snack that is healthy. And you have to admit, doesn’t a bucket of fried chicken and some mashed potatoes and gravy from KFC sound tasty? A lot of people take comfort in the taste of these rich, heavy foods. They find their favorite snack from McDonald’s welcoming. And Taco Bell does have that great value menu, don’t they? It’s just too easy to get roped into that trap. Even if people aren’t eating fast food, I’m sure most of us are guilty of buying the frozen Banquet dinners at WalMart (hey, they’re $1, and with a 2 year old…I don’t have time in the mornings to pack my lunch), or sending the Lunchables to school for their kids. It’s so much easier to boil a few hot dogs for dinner. We are surrounded by all these foods supposedly made to make our lives easier. At the same times, these foods are making us unhealthier, so where is the convenience in the long run?
Eating healthy takes work. Unfortunately, the healthier choices are often the more expensive ones. I’m sure all of us would like to have the time to eat our three square meals a day, with all the fruits and vegetables that we need. There are some people that are fortunate enough to stay at home and have plenty of time to do just that. I know if I didn’t have to work, I would prepare better meals for my family. There are ways to try and eat a little healthier. One thing my family does is try to keep a variety of fresh fruits on hand. That way, if we are hungry, we can grab an apple, or a pear instead of a handful of chips to munch. The majority of Americans do not have a well balanced diet. There are so many people following these fad diets, and these aren’t well balanced. They either limit your carbohydrates, limit your protein, or other things, all of which are essential in at least some small form. Americans have become such soda junkies as well. I know very few people that drink the recommended eight glasses of water each day. I think that deep down, most of us want to do the right thing as far as our diets go, but most of us struggle to find that balance between eating the right kind of foods and having the time to relax that we so desire at the end of a long day.
I personally think too many people go the fast food route, and I think that has a great deal to do with laziness. I like my fast food, but in my family, we limit it to maybe once a month. I work full time and my husband is a full time nursing student. We have a two year old daughter. When we get home, both of us are exhausted. I have to say that my husband and I are guilty of throwing together convenience foods for ourselves for dinner, but I can be proud to say that at least we make sure our daughter is eating a well balanced diet. She is better than the two of us, and actually prefers fresh fruit and vegetables to junk food. She actually was unhappy last night because we went to the mall and got her a Sonic Kids meal while we were there. They have a picture that says they offer string cheese with their kids meals. They don’t really have it…the picture is just promotional. My daughter HATES fries and tater tots. I ended up going to Subway and getting her a bag of sliced apples to go with her chicken. I think most fast food chains are trying to do their part in offering healthy alternatives. It is hard to eat healthy when you are on the go so much, but it is possible to keep healthier snacks on hand.
I’m honestly not sure what’s in store as far as this problem goes in the future. The problem of obesity continues to rise, yet fast food franchises recognize this problem and are trying to offer healthier choices such as salads and fruits on their menus. The question is, how much do we want to change? Some people are stubborn and go to these fast food restaurants to get their “comfort” foods and don’t consider a nice salad to fulfill that need. It is an individual choice, and those that really want to change can do so, but it is all up to them.

I used images from the following locations

http://vagabondrunn.files.wordpress.com/2008/06/fast-food.jpg

http://www.freewebs.com/julatradeexports/a11.jpg

A Day of Food

2008-10-06T21:00:00.000-07:00

Okay, once again, I tried step by step to copy the webpage, and it wouldn't let me, so I am again going with a screen shot taken by my digital camera. Since the image isn't perfectly clear, I will also list the results.

My diet today consisted of

Breakfast :

1 cup of regular coffee

1 bowl of fruit oatmeal

Lunch :

1 small grilled steak

vegetable pasta salad

water

Snack :

1 piece of marble cake

Dinner:

popcorn chicken

tater tots

water

I had a total intake of 1640 calories. Calories from fat were 860. My total fat was the only high area, at 148% of the recommended daily allowance. Saturated Fat 85%

Trans Fat 0g

Cholesterol 37%

Sodium 98%

Carbohydrates 44%

Dietary Fiber 32%

Protein 68g

Vitamin A 6%

Vitamin C 25%

Calcium 15%

Iron 40%

I think today's diet was fairly decent, although I am obviously lacking in my vitamin intake. I know the total fat was a little high. I confess that's due to stopping at Sonic for dinner tonight, which fortunately, is a rare occasion. I normally am a big milk drinker but was on the go all day today and didn't drink my milk at all. I would normally not eat fast food, my husband and I try to cook our dinners at home. I need to add more fruits and vegetables to my diet. I had no vegetables today other than what was in the pasta salad, and no fruit other than the dried strawberries in my oatmeal. I think this type of tracking is beneficial because it lets you see which areas that you are taking in excess amounts, and which areas are lacking.

Unit 2 Compendium Review - Major Topic 2

2008-10-01T20:36:00.000-07:00

Compendium Review Unit 2 Major Topic 2
I.Digestive System and Nutrition
A. Overview
1.ingestion
2. digestion
3. movement
4. absorption
5. elimination
B. Beginning of Digestive tract
1.mouth
2. pharynx
3. esophagus
C. Stomach and Small Intestine
1. lactose intolerance
2. obesity and diabetes
D. Accessory organs and regulation of secretions
1. pancreas
2. liver
3. bladder
4. regulation of digestive secretions
E. Large intestine
1. disorders
F. Nutrition and weight control
1. obesity
2. classes of nutrients
a. carbohydrates
b. lipids
c. proteins
3. minerals and vitamins
4. eating disorders
There are several small processes necessary in order to complete the larger process of digestion. The first of these processes is called ingestion, which is what happens when food is taken in through the mouth. Digestion is the next phase and can be either mechanical or chemical. The mechanical part of digestion occurs in the mouth and stomach, and chemical digestion begins in the mouth and ends when food reaches the small intestine. Next is movement of the GI tract which passes food from one organ to the next. Fourth is absorption as molecules produced by digestion cross the GI tract wall and enter the cells. Finally, is elimination, in which molecules that cannot be digested are eliminated from the body through the anus.
The GI tract begins at the mouth and ends at the anus. The central space of the GI tract is the lumen which contains water, or the food that is being digested. The first layer of the wall is the mucosa. The other three layers are the submucosa, the muscularis, and the serosa.
The digestive tract begins with the mouth. The roof of the mouth has a hard palate, containing several bones, and a soft palate which ends in a projection called the uvula. There are three pairs of salivary glands which send juices to the mouth. Mechanical digestion is performed by our teeth and our tongue, when we chew food to prepare it for digestion. The tongue houses the taste buds which send nerve impulses to the brain.
The mouth leads to a cavity called the pharynx. This is where the food and air passages cross. When you swallow, food enters the esophagus, which takes food to the stomach. We cannot breathe simultaneously to swallowing. Peristalsis is a rhythmic contraction which pushes food along the esophagus.
Our stomach is an organ shaped like the letter J, that is on the left side of the body beneath the diaphragm. The stomach stores the food and initiates the digestion of protein. It also controls how chime moves into the small intestine. The stomach has gastric juice with an enzyme called pepsin, which digests protein, hydrochloric acid, and mucus. The stomach usually empties in two to six hours. The small intestine averages eighteen feet in length. The first twenty five centimeters of the small intestine is the duodenum. A duct brings bile into the duodenum, and emulsifies fat. Digestion is completed, and nutrients are absorbed in the small intestine.
The primary sugar in milk is called lactose. People without the enzyme cannot digest lactose and are known as being lactose intolerant. The nutrients that are absorbed in the small intestine can affect our health. The intake of too much sugar can lead to obesity which can lead to diabetes type two, and cardiovascular disease.
The pancreas is located behind the stomach. It is an endocrine gland that secretes insulin into the blood. The liver is the largest metabolic gland in the body. It is a storage organ, removing the vitamins A, D, E, K, and B12 from the blood and storing them. The liver produces bile salts. Hepatitis is a serious disease that affects the liver. It occurs when the liver is inflamed. Cirrhosis is when the liver becomes fatty and replaced by scar tissue.
Our large intestine absorbs water, helping to prevent dehydration of the body. The large intestine is where feces are formed. Feces are made up of one quarter solids and three quarters water. Indigestible materials are in the solid part of feces. Defecation is the process of ridding the body of feces. There are several common disorders of the colon and rectum. Among these are diarrhea, constipation, diverticulosis, irritable bowel syndrome, and inflammatory bowel disease.
Obesity is a rapidly growing problem in the United States. It is defined as the condition of being grossly overweight. It is recognized as having a body mass index of 32 or greater. Your BMI gives you an idea as to how much of your weight is due to adipose tissue, or fat.
Nutrients are what provide us with energy, promote growth and development, and regulate cellular metabolism. Carbohydrates are one form of nutrients. They are either simple or complex. Any product that is made of refined grains should be limited in intake. Proteins are digested to amino acids. These are not stored in the body, therefore it is important to eat a daily supply. Lipids are fats, oil, and cholesterol. Minerals are divided into two groups : major minerals and trace minerals. Calcium and sodium are two of the major minerals. Calcium is very important for the formation of bones and teeth. Sodium helps regulate the body’s water balance.
Vitamins are organic compounds used for metabolic purposes. The body need these but cannot produce an adequate amount. Antioxidants, such as vitamins C, E, and A defend the body against free radicals. Vitamin D helps with the skin and with calcium absorption.
It is very important to eat nutritious meals to ensure that your body gets what it needs to properly perform all of its functions. The US Department of Agriculture encourages us to eat a variety of foods. People with eating disorders are usually in this state because they aren’t satisfied with the way their body looks. Anorexia nervosa is a fear of getting fat, causing the person to not eat enough food to keep up a healthy body weight. Bulimia nervosa causes a person to binge eat and then purge to avoid gaining weight.

http://www.johnmccraess.ocdsb.ca/PROJECTS/Science/DigestionWeb/humandigest.gif

http://www.nlm.nih.gov/MEDLINEPLUS/ency/images/ency/fullsize/8880.jpg

http://www.mydr.com.au/content/images/categories/gastro/stomach_normal.gif

http://www.clarian.org/ADAM/doc/graphics/images/en/19200.jpg

http://medicalimages.allrefer.com/large/obesity-and-health.jpg

http://www.diseaseeducation.com/images/Disease1.gif

Blood Pressure Lab

2008-09-29T20:30:00.000-07:00

Journal question 1
As a person gets older, the risk of high blood pressure is greater. Men have a slightly greater risk than females.

Journal question 2
If the majority of the people in a group are older, or more are males, the average blood pressure for the group would be higher than if the group was younger and consisted of more females.

Journal question 3
I will first go through and test all the age ranges for the females, finding the average systolic and diastolic pressures. I will then repeat the process for the males, and chart my findings.

Journal question 4
The pattern I observed was that the average systolic and diastolic blood pressure incresed with age, especially in the males. The female's varied more, but the risk of high blood pressure was still the greatest in the oldest age group.

Journal question 5
The result of my experiment clearly supported my hypothesis. The risk of high blood pressure increased with age, and the average for the males was higher than the females.

Journal question 6
Poor diet, alcohol consumption, lack of exercise, and family history usually played a factor in the people that were outside the normal range. People that were overweight also had higher blood pressure

Journal question 7
family history, high salt diet, lack of exercise, alcohol consumption. I think a high salt diet is most closely observed with hypertension.

Journal question 8
Obesity alone does not cause a person to be at risk for high blood pressure. A person's diet and activity level can play a part in adding to the person's risk.
Table
For some reason, blogger is giving me trouble tonight - I will post my table and graph as soon as it will let me

Compendium Review Unit 2 Major Topic 1

2008-09-28T14:30:00.000-07:00

Compendium Review Unit 2 Major Topic One

I. Cardiovascular system - heart and blood vessels
A. Functions
1. contractions generate blood pressure
2. blood vessels transport blood
3. exchanges at capillaries refresh blood and tissue fluid
4. heart and blood vessels regulate blood flow
B. Lymphatic System
C. Types of Blood Vessels
1. arteries
2. capillaries
3. veins
D. heart is a double pump
1. route of blood through the heart
2. controlled heartbeat
a. internal
b. external
3. electrocardiogram
E. Pulse and heart rate
F. Regulation of blood flow
G. Pulmonary Circuit
H. Systemic Circuit
I. Cardiovascular Disorders
1. high blood pressure
2. stroke and heart attack
3. treatments
4. heart disorders
II. Cardiovascular System - blood
A. Functions
B. Composition
1. plasma
C. Red Blood Cells
1. transport
2. disorders
D. White Blood Cells
1. types
2. disorders
E. Blood clotting
1. disorders
F. Blood typing
1. ABO
2. Rh
G. Homeostasis
III. Lymphatic System / Immunity
A. Bacteria
B. Viruses
C. Prions
D. Lymphatic System
1. vessels
2. organs
E. nonspecific defenses
1. barriers
2. inflammatory response
F. specific defenses
1. antibodies
2. T cells
G. Acquired Immunity
1. active
2. passive
H. Hypersensitivity
1. allergies
2. disorders
IV. AIDS
A. Origin of AIDS
1. prevalence
B. phases of HIV infection
1. acute
2. chronic
3. AIDS
C. HIV structure and life cycle
D. testing and treatment

The cardiovascular system contains the heart and the blood vessels. The main function of the heart is to pump blood, and the blood flows through the blood vessels. The true purpose of circulating blood is to service the cells. Cells are surrounded by tissue fluid. Blood exchanges substances indirectly with the cells by exchanging with tissue fluid. Blood removes waste products from the tissue fluid, and brings the tissue fluid oxygen and nutrients to keep the cells functioning. At the lungs, carbon dioxide leaves the blood, and oxygen enters the blood. There are four main functions of the cardiovascular system. First of all, contractions of the heart are what generates blood pressure. Second, blood vessels transport the blood. Third, exchanges at the capillaries refresh the blood and the tissue fluid. Lastly, the heart and the blood vessels regulate blood flow. The lymphatic system plays an important role in the functioning of the cardiovascular system because the lymphatic vessels collect the excess tissue fluid and return it to the cardiovascular system.
There are three types of blood vessels : arteries, capillaries, and veins. The walls of an artery have three layers...the endothelium, smooth muscle, and connective tissue. Arterioles are small arteries that we can see. The arteries move blood away from the heart. The arteries then branch into blood vessels known as the capillaries. These are microscopic tubes that are made up of only endothelium with a basement membrane. Capillaries are present everywhere in the body. The veins have valves that control the direction of the flow of blood. Seventy percent of blood is in the veins at any given time.
The heart is cone shaped and is located between the lungs. The major part consists mainly of cardiac muscle tissue, and is called the myocardium. The pericardium surrounds the heart. Inside the heart, there is a wall called a septum, that separates it into the right and left sides. The heart has four chambers. The upper chambers are called the atrium, and the lower are the ventricles.
There is a specific path blood follows when it flows through the heart. The following is direct from the textbook, page 89.

-The superior vena cava and the inferior vena cava, which carry 02 poor blood, enter the right atrium.
- The right atrium sends blood through an atrioventricular valve (the tricuspid valve) to the right ventricle
- the right ventricle sends blood through the pulmonary semilunar valve into the pulmonary trunk. The pulmonary trunk, which carries O2 poor blood, eivides into two pulmonary arteries, which go to the lungs
-Four pulmonary veins, which carry O2 rich blood, enter the left artium
-the left atrium sends blood through an atrioventricular valve (the bicuspid [mitral] valve) to the left ventricle
-the left ventricle sends blood through the aortic semilunar valve into the aorta to the body proper

Oxygen poor blood is always kept separate from the oxygen rich blood. The left side of the heart is the stronger pump, causing blood pressure to be greatest in the aorta.
Every heartbeat is known as a cardiac cycle. Systole, or the working phase, happens when the chambers contract. Diastole, or the resting phase, is when the chambers relax. The heart beats about seventy times a minute. Internal nodes are what control the rhythmical contraction of the atria and ventricles. The sinoatrial node is known as the pacemaker because it regulates the heartbeats. The heartbeat can also be regulated by external means such as when we exercise. It is possible to get a recording of electrical changes in the heart. This recording is called an electrocardiogram, or an ECG.
Your pulse rate is the same as your heart rate. The pulse is the rhythmic expansion and recoil of an arterial wall. The beating of the heart creates pressure which sends blood to arteries and arterioles. This pressure is called blood pressure. Systolic pressure is the highest arterial pressure and happens when blood is ejected from the heart. Diastolic pressure is the lowest pressure and occurs while the ventricles are relaxing. Normal adult systolic pressure should be between 95 and 135, while diastolic should be between 50 and 90.
There are two circuits that allow blood to flow through. These are the pulmonary circuit, which exchanges gases, and they systemic circuit which exchanges with tissue fluid. The coronary arteries are the first branches off of the aorta and serve the actual heart muscle. Blood pressure and osmotic pressure are what control the movement of fluid through the capillary wall.
Cardiovascular disease is the leading cause of early death among Western countries. Hypertension, also known as high blood pressure, can be deadly because it often is not found until it has caused a heart attack or a stroke. This can usually be controlled by living a healthier lifestyle to include not smoking, and eating a healthy diet. Clogged arteries are another disease and can be treated by a coronary bypass operation to remove plaque from the arteries.
Heart failure occurs when a person's heart fails to pump as it should. It is possible to have a heart transplant, but unfortunately, there are far more people needing hearts than there are available donors.
There are approximately five liters of blood in the human body. The heart pumps this amount every time it beats. Blood defends the body against pathogen invasions. Some blood cells destroy pathogens while others produce antibodies. Blood also clots to prevent blood loss. Blood also helps regulate body temperature by picking up heat.
Blood has multiple components. The formed elements are red blood cells, white blood cells, and platelets. These are all formed in red bone marrow. Red blood cells are more abundant than white blood cells, but are smaller in size. Plasma is the liquid that carries substances in the blood. Plasma is made up of 91% water. There are three main types of plasma proteins : albumins, globulins, and fibrinogen.
Red blood cells are also called erythrocytes. They are small disks that do not have a nucleus. They are needed for oxygen transport. They carry hemoglobin instead of having a nucleus. Hemoglobin is what gives blood its red color. Blood picks up carbon dioxide in the tissue, and seven percent is dissolved in the plasma. Hemoglobin directly transports 25%. The rest is transported in the plasma. About two million red blood cells are destroyed per second, and the body has to produce new ones at the same rate. When insufficient oxygen is being delivered to the cells, erythropoietin is released by the kidneys and stimulates the stem cells in the bone marrow to produce more red blood cells. An insufficient number of red blood cells is known as anemia, which can be caused by an iron deficiency.
White blood cells are known as leukocytes. They have a nucleus and lack hemoglobin. They are translucent unless they have been stained. White blood cells are a very important part of the immune system because their main function is to fight infection. There are two types of white blood cells : granular leukocytes which include neutrophils. eosinophils, and basophils; and agranular leukocytes which include lymphocytes, and monocytes. One of the better known disorders having to do with white blood cells is leukemia. Leukemia is cancer of the blood cells.
Platelets are also known as thrombocytes and are responsible for the clotting of blood. When a blood vessel is damaged. platelets combine together to stop the bleeding. An inherited disorder that keeps blood from clotting is called hemophilia.
Everybody has a certain blood type. If you have type A blood, then your body has anti-B antibodies in the plasma, which would keep a blood transfusion that didn't match your blood type from being successful. Type O blood is also known as the universal donor, because it will not cause agglutination with any blood type. If a women does not have the Rh factor in her blood, and the father does, it can be passed through the placenta from the fetus to the mother. This can destroy blood cells. An Rh negative woman needs to have an immunoglobulin injection within 72 hours of giving birth to an Rh positive child.
Homeostasis is made possible by the cardiovascular system delivering oxygen from the lungs and nutrients from the digestive system, and the lymphatic system returning tissue fluid to the bloodstream.
The human body has three barriers of defense against invasions by pathogens. First of all, barriers such as the skin and mucous membranes, prevent entry. Phagocytic white blood cells help prevent infection after an invasion. Specific defenses overtake the infection by killing the disease causing agent.
One of the main types of pathogens is bacteria. These are single celled prokaryotes which lack a nucleus. There are three common shapes of a bacterium : bacillus, coccus, and spirillum. Bacteria are independent and metabolically competent. Some have plasmids, or accessory rings of DNA. This is where the genes that allow bacteria to be resistant to antibiotics are often located. Another pathogen is a virus which bridges the gap between living and nonliving. When a virus replicates inside a cell, they appear alive. Viruses are four times smaller than a bacteria. They take over the metabolic machinery of a host cell.
The lymphatic system is made up of vessels and organs. Lymph, a colorless liquid, is the fluid inside lymphatic vessels. Lymphatic organs consist of red bone marrow, the thymus gland, lymph nodes, and the spleen. Red bone marrow is where blood cells are produced. The thymus gland produces hormones and it is also the place where T lymphocytes go to mature. The spleen’s purpose is to filter blood, and lymph nodes filter lymph.
Immunity is the ability to combat disease. The body has several built in barriers to try and prevent invasion by pathogens. Some of these include the skin and mucous membranes, sebaceous glands, and normal flora. The body’s second line of defense is known as the inflammatory response. Chemical mediators are released by damaged tissue cells causing the capillaries to dilate. More blood flows through these, increasing temperature, which inhibits the growth of some pathogens.
Certain types of defenses respond to antigens. These depend on either B cells or T cells which recognize antigens. There are five different classes of antibodies. T cells recognize antigens without any help. Helper T cells regulate immunity. Memory T cells serve the purpose of just what they sound like – they remember pathogens that have been in the body before and can jumpstart an immune reaction.
Active immunity occurs when a person is well and can be vaccinated, or immunized, against an infection in order to prevent it. Passive immunity is when a person is given immune cells to fight off a disease.
Allergies are when the body is hypersensitive to specific substances. Common allergens are pollen, food, or animal hair. Allergic reactions tend to include tissue damage. A severe allergic reaction is anaphylactic shock.
A person with an autoimmune disease suffers because antibodies wrongly attack the body’s own cells, thinking that they contain foreign antigens.
One of the worst autoimmune diseases worldwide today, is AIDS, or Acquired immunodeficiency syndrome which is caused by a virus called human immunodeficiency virus, or HIV. HIV originated in Africa and spread to the United States through the Caribbean. The name AIDS was not coined until 1982. AIDS is considered a pandemic because it is a global condition.
There are three phases of HIV infection. The first phase is acute phase. The person in this phase usually has no symptoms and is highly infectious. Their CD4 T cell count has not yet fallen below 500 cells per cubic millimeter. The next phase is chronic phase. This person has a CD4 T cell count between 499 and 200 cells per cubic millimeter. They have begun to show several symptoms common to a suffering immune system. The final category is AIDS. This is when the CD4 T cell count is below 200 cells and the person has developed one or more of the opportunistic infections described by the CDC’s list of conditions for AIDS definition. Death usually follows within two to four years of this final phase.
HIV can be transmitted by sexual contact or by needle sharing between intravenous drug users. The bodily fluids with the highest concentration of HIV include blood, semen, vaginal fluid, and breast milk.
There is no cure for AIDS. There is, however, ongoing research that hopes to make a vaccination available possibly as soon as the year 2010.

Aside from the textbook, I used the following web sources

http://homepages.wmich.edu/~p3morefi/heart.jpeg

http://www.sci.sdsu.edu/class/bio590/pictures/lect5/artery-vein.jpeg

http://www.starsandseas.com/SAS_Images/SAS_Physiol_Images/SAS%20cardiopics/heart_chambers.jpg

http://www.castlefordschools.com/kent/07-08%20lessons/Lessons/Advanced%20Biology%20Lessons/chapter%2038/Advanced%20Biology%20Chapter%2038%20Circulatory%20and%20Respiratory%20Systems_files/image036.jpg

http://www.biotech-weblog.com/50226711/images/atherosclerosis.jpg

http://medicalimages.allrefer.com/large/ecg.jpg

http://www.nlm.nih.gov/MEDLINEPLUS/ency/images/ency/fullsize/9123.jpg
http://static.howstuffworks.com/gif/adam/images/en/blood-types-picture.jpg

http://ucatlas.ucsc.edu/health/aids/images/AIDS_Map_Adults1.gif

http://www.norcalblogs.com/watts/images/GeneralBacteria.jpg

http://www.nytimes.com/imagepages/2007/08/01/health/adam/19150Allergicreactions.html

Self and Unit Evaluation 1

2008-09-19T21:03:00.000-07:00

Self
The three thins I am proudest of from this unit are: my cell model...I think mine turned out pretty unique in that not only did the materials I used resemble the parts of a cell, they also served similar functions; my use of images in all my posts; and the fact that I only had after 8:30 pm every night to work on homework and still accomplished everything on time. The two aspects that can use improvement are probably my compendium reviews could be better organized, and I need to figure out how to use blogger.com better so that my blogs have a neater appearance. Overall, I think my grade should be somewhere around an a-. I am hoping to have more time to work on the overall presentation of my blogs for the next unit.

Unit
I felt most engaged in this unit while doing the genetics lab. I thought the Punnett Squares were enjoyable, and would have enjoyed a more in depth lab. I was most distanced during the reading about the cell parts and functions. I really like the fact that Professor Frolich responds so quickly to any email questions and concerns. The thing I found most puzzling was when I went to look at classmates blogs, there were only a few to look at other than my own. I'm not criticizing, some people work better under last minute pressure. I was surprised at how interesting most of this unit was, being that science has never been a subject of interest for me.

Ethical Issue Essay Unit 1

2008-09-19T20:30:00.000-07:00

Ethical Issue Essay...Unit 1
What is cloning? Cloning is the a possibility that was first raised when Scottish scientists created the sheep, Dolly, in 1997. There are three different types of cloning. The first is called recombinant DNA technology. This is when scientists transfer a DNA fragment of interest to bacterial plasmid. Plasmids carry up to 20,000 bb of foreign DNA. The second type of cloning is known as reproductive cloning. This is when scientists are able to generate an animal with the same nuclear DNA as a current or previously existing animal. An animal created this way is not really an identical clone of the donor animal, as is the popular belief. The only part that is identical to the donor animal is the chromosomal or nuclear DNA in the clone. Last is therapeutic cloning. This is the production of human embryos to harvest stem cells to study human development and treat disease.
Scientists feel that they are making a major breakthrough, particularly in medicine with all of their advances in genetic engineering. There are several benefits to each of the different types of cloning. Recombinant DNA technology is beneficial because it is important to learn about other related technology. Reproductive cloning is used to develop ways to reproduce animals with special or unique qualities to be used for certain purposes and also to repopulate animal species that are endangered. Therapeutic cloning can be used to produce whole organs from single cells or even to produce healthy cells where disease has affected the body.
However, there are many risks to all forms of genetic cloning. Reproductive cloning only has a ten percent success rate. Even the ten percent of cloned animals that are successful tend to have a much higher rate of disorders, disease, and mutations. The first time a an endangered wild animal was born was in 2001. It was a wild ox known as a gaur. It got an immediate infection and died only forty eight hours after it was born. The American Medical Association, or AMA, and the American Association for the Advancement of Science advise against reproductive cloning. They believe it is highly expensive and overall, ineffeficient. U.S. Congress is considering legislation to ban the process of reproductive cloning in our country. Greenpeace is also strongly against any form of genetic engineering. They state that genetically modified organisms can spread out and breed with natural organisms, thereby contaminating future generations.
Both sides of the debate about genetic engineering have valid points. It has both strengths and weaknesses, and who am I to say which outweighs the other.
I see the debate on cloning going on for many, many more years. I think that before it is accepted by mainstream community, much more research has to be done. The general public is not going to accept cloning when it is so expensive and has a ninety percent rate of failure... I think, however, that when scientists progress further with it, and improve technology, as is always happening, that it might become easier accepted.

Unit 1 Cell Model

2008-09-18T21:27:00.000-07:00

The picture on the left is the materials I used to make my cell, and the picture below is a view of the completed cell

3(1) closeup of vesicles, lysosomes, and golgi apparatus

(2)closeup of mitochondria, rough endoplasmic reticulum, and nucleus)

3(another view of the completed cell)

I enjoyed creating a model of a cell. I tried to find materials that not only looked like the part of the cell they were supposed to represent, but also served a similar function as what they represented. Here are the items I used, and why :

Cell membrane - wire looming. The cell membrane holds everything in the cell and controls what enters and leaves the cell.

Nucleus - a CD. The nucleus contains all the DNA and genetic information, much as a CD contains and stores information.

Mitochondria - batteries. The mitochondria is the powerhouse of the cell, much as batteries are the powerhouse of many products.

Golgi apparatus - divided container. The golgi apparatus processes, packages, and secretes cell products. A divided container can also be used to process and package items.

Lysosomes - my daughter's recycle truck, dump truck, and roadkill removal van. The lysosomes are used for waste disposal, and recycling which is the same function of each of the vehicles.

Vesicles - my daughter's pickup truck and bicycle hauler. The vesicles store and transport substances similar to the way you can transport items in either of my daughter's vehicles.

Flagella - end piece of wire looming, with toothpicks inside to represent the microtubules. The flagella is resposnsible for cell movement.

Smooth Endoplasmic reticulum - green tea tablets. Smooth ER is used to synthesize fat, and green tea tablets are a weight (fat) loss aid.

Rough Endoplasmic reticulum - plastic animals that are prey in the wild. The Rough ER contains the proteins. Prey contain proteins for their predators.

Ribosomes - plastic animals that are predators in the wild. The ribosomes synthesize proteins...in my model the predators are feasting on the prey, synthesizing their proteins.

Other parts - nucleolus - ball from one of my daughter's toys

chromatin - rice

DNA is a double helix, made up of two strands spiraling around each other. It's structure resembles a ladder, with the rungs being the paired bases. The bases in DNA are Adenine and Thymine along with Guanine and Cytosine. The strands of the double helix are made of playdoh, and the bases are different colored marshmallows.

There are four main phasesof mitosis : prophase, metaphase, anaphase, and telophase. I illustrated each of the phases using these materials : red and blue Playdoh for the chromatin, macaroni noodles for the spindle poles, toothpicks for the spindle fibers, green playdoh for the nucleolus and playdoh lids for the nuclei.

During prophase, the centrosomes outside the nucleus have duplicated and begin to move toward opposite ends of the nucleus. The spindle fibers begin to form.

During Metaphase, the centromeres of the duplicated chromosomes line up at the equator. There are spindle fibers attached to the sister chromatids.

During Anaphase, the sister chromatids part and become daughter chromosomes. These move toward the spindle poles.

During Telophase, the daughter cells form as nuclear envelopes and nucleoli reappear.

This was a fun project, and I enjoyed the chance to be creative.

Compendium Review Unit 1 Main Topic 2

2008-09-15T20:59:00.000-07:00

Compendium Review Unit 1 Major Topic 2
I. Patterns of Chromosome Inheritance
A. Cell Cycle
1.karyotype
2. cycle
B. Mitosis
1.overview
a. prophase
b. metaphase
c. anaphase
d. telephase
2. cytokinesis
C. Meiosis
1. stages
D. Comparison of meiosis and mitosis
1. spermatogenesis and oogenesis
E. Chromosome Inheritance
1. changes in number
2. chromosomal disorders
3. changes in structure
II. Cancer
A. characteristics of cancer cells
1. genetic disease
2. types of cancer
a. carcinomas
b. sarcomas
c. leukemias
d. lymphomas
B. Causes and Prevention
1. heredity
2. environmental carcinogens
3. dietary
C. Diagnosis
1. warning signs
2. screening tests
3. tumor marker tests
4. genetic tests
D. Treatment of Cancer
1. surgery
2. radiation
3. chemotherapy
4. newer therapies
III. Patterns of Genetic inheritance
A. Genotype and phenotype
B. One and two trait inheritance
1. forming gametes
2. one trait crosses
3. two trait crosses
4. family pedigrees for genetic disorders
5. genetic disorders
C. Beyond Simple Inheritance Patterns
1. polygenic inheritance
2. incomplete dominance and codominance
3. multiple allele inheritance
D. sex linked inheritance
1. x-linked alleles
2. x-linked disorders
IV. DNA Biology and Technology
A.DNA and RNA structure and function
1. structure of DNA
2. replication of DNA
3. structure and function of RNA
a. ribosomal RNA
b. messenger RNA
c. transfer RNA
B. Gene Expression
1. structure and function of proteins
2. gene expression
3. transcription
4. translation
5. regulation
C. Genomes
1. sequence of human genome
2. functional and comparative genomics
3. proteomics and bioinformatics
4. modifying human genome
D. DNA Technology
1. isolating and cloning genes
2. cloning specific DNA sequences
3. biotechnology products

Humans have a total of 46 chromosomes. They are paired up, giving us 23 pairs. Twenty two of these pairs are called autosomes and control traits that have nothing to do with a person's gender. The other pair is called the sex chromosomes because they do determine gender. Males are X and Y, and females are X and X.

picture is of human chromosomes

Karyotypes tell us about cells in the body. A normal body cell has all forty six chromosomes. Mitosis is the process that ensures that every cell has this number. When cells divide, each chromosome is composed of two parts that are identical, called sister chromatids. These contain a DNA double helix. The chromatids are connected at a place called the centromere until the phase of mitiosis in whcih it splits.
The cell cycle has two parts. These are called interphase and cell division. Most of the cell cycle is spent in interphase which is broken down into three parts. The organelles carry on their usual functions during this time.

The first stage is known as the G1 stage. The cell doubles its organelles and gathers the materials needed to synthesize DNA. Next is the S stage in which DNA replication occurs, duplicating the chromosomes. In the G2 stage, the cell synthesizes the proteins that are needed for the cell division. After interphase, the cell begins dividing. The first part of this is called M (for mytotic), and cytokinesis. Mitosis is the nuclear division and cytokinesis is division of the cytoplasm. There is a process called apoptosis which is programmed cell death, which occurs to get rid of cells that are dividing when they shouldn't be.
Mitosis is known as duplication division. The nucleus in both of the new cells have the exact same number and types of chromosomes as the cell that divides. The cell that divides is the parent cell, and the daughter cells are the new cells. When mitosis is about to occur, the chromatin in the nucleus becomes condensed. The centrosomes duplicate and then separate forming the poles of the mitotic spindle. There are four phases of mitosis. The first, prophase, visibly indicate that the cell is ready to divide. Spindle fibers begin to appear and the nuclear envelope begins to split apart. The nucleolus disappears. The chromosomes shorten and thicken and spindle fibers attach to the centromeres. In the next phase, metaphase, the spindle occupies where the nucleus was. The chromosomes are at the center, each with two sister chromatids. In anaphase, the third phase, the centromeres divide, followed by the sister chromatids. The diploid chromosomes move toward each pole. Last is telophase which happens when the chromosomes reach the poles. There they once again become chromatin. The spindles disappear and the nuclear envelope reforms. There are now two daughter nuclei. In cytokinesis, the cytoplasm and the organelles divide, resulting in each cell being enclosed by its own plasma membrane. The cell cycle is very important to a human's well being. It kicks in to repair injuries, and to help us grow.
Meiosis is known as reduction division, involving four daughter cells.

Each daughter cell has half as many chromosomes as the parent cell. The parent cells has 2n, or the diploid number of chromosomes, and the daughter cells have n, the haploid number. When meiosis begins, the chromosomes occur in pairs and are called homologues. The divisions of meiosis are meiosis I and meiosis II. During the first one, the chromosomes line up side by side resulting in four chromatids that stay close together. This is called a synapsis. Following this is interkinesis, immediately followed by meiosis II. The centromeres divide and the sister chromatids become chromosomes that are passed on to daughter nuclei. In the end of this process, all four daughter cells have the n number of chromosomes, containing one chromatid. In humans, these cells mature into gametes, sperm and egg), that will fuse during fertilization. Meiosis is part of sexual reproduction. Meiosis I and II both go through the same four stages of nuclear division as mitosis. In prophase I, the spindle appears and synapsis occurs. The homologous chromosomes line up next to each other. This is when an exchange of genetic material may occur. During metaphase I, the homologous pairs line up by themselves at the equator. The events of these two phases ensure that gametes will not have the same chromosomes and genes.
Meiosis is significant because it is a part of production of sperm and egg. It keeps the chromosome number the same from generation to generation. Even though both mitosis and meiosis are nuclear divisions, there are several differences between the two. Meiosis requires two nuclear divisions while mitosis requires only one. Meiosis produces four daughter cells, mitosis only two. The daughter cells that result from meiosis are haploid, and the daughter cells following mitosis are diploid. The daughter cells from meiosis are not identical to the parent cell. Mitosis occurs in all tissues during growth and repair. Meiosis occurs only at certain times during the life cycle. Meiosis is part of spermatogenesis and oogenesis, the production of sperm and eggs.
People sometimes are born with too many or too few sex chromosomes. Aout of all autosomal trisomies, only Down syndrome, Trisomy 21, has a good chance of surviving after birth. People with Down syndrome have three copies of chromosome 21. Chances of a woman having a child born with Down syndrome increase rapidly with age. People with Down syndrome have the following characteristics...short stature, flat face, stubby finger, and the so called simian line. Mental retardation is unfortunately an accompanying part of Down syndrome though the severity of it varies greatly.
Turner syndrome is a syndrome in whcich the individual only has an X chromosome.. Adult females with Turner syndrome are short and have a broad chest with folds of skin on the backs of their necks. They do not undergo puberty or menstruate.
Klinefelter syndrome is when a male is born with two X chromosomes and one Y chromosome. The symptoms are very subtle. There may be some delays with speech and language.
A female with more than two X chromosomes have Poly X. Jacobs Syndrome occurs when males have an X chromosome and two Y chromosomes. They are usually of above average height and have speech problems.
Other chromosomal disorders can occur when there is a change to chromosome structure. There are several types of changes that can occur. A deletion is when an end of a chromosome breaks off. A duplication is when a chromosomal segment appears more than once. An inversion is when a segment of the chromosome is turned 180 degrees. A translocation is when a segment moves from one chromosome to another. A deletion can cause a syndrome such as Williams syndrome. Children with this syndrome are said to have the appearance of pixies and have excellent verbal and musical skills.
Cancer envelopes more than a hundred different diseases, but they all have similarities. Cancer cells do not look like any other cells, and they do not contribute to any function in the body. They have enlarged nuclei and may contain more chromosomes. They are immortal and divide an infinite number of times. They pile together and form a tumor. They don't need growth factors and continuously divide. They gradually become abnormal.

picture is of a dividing cancer cell

Cancer is a genetic disease. Oncology is the study of cancer. Oncologists classify cancer according to the place it originates. There are four main types. Carcinomas are of the epithelial tissues. Sarcomas are found in muscles and connective tissue. Leukemias are found in blood. Lymphomas are in the lymphatic tissue. Lung cancer is one of the most common types of cancer. Another common type is colorectal, or cancer of the colon/rectum. My grandmother was diagnosed with colorectal cancer at the age of 73, and four years later was in remission. Around the age of 81, she was diagnosed with kidney cancer, and again a couple years later was in remission. She will be 85 next month and shows no signs of cancer.
Cancer can be hereditary. It can also be caused by environmental carcinogens such as radiation and organic chemicals. Diagnostic x rays account for most of a person's exposure to artificial radiation. Tobacco smoke and pollutants are very harmful. DNA viruses are also directly believed to cause cancer. Nutrition can help a person prevent cancer.
Seven warning signs can help us become aware of whether we need to be concerned. These can be remembered by the word CAUTION. Change in bowel or bladder habits, A sore that does not heal, Unusual bleeding or discharge, Thickening or lump in breast or elsewhere, Indigestion or difficulty in swallowing, Obvious change in wart or mole, Nagging cough or hoarseness.
There are several tests that can help diagnosis cancer. The earlier a cancer is found, the better the chance for effective treatment. Routine screening tests, by yourself, and by your physician help to detect the presence of cancer early. Tumor marker tests test the blood for tumor antigens and antibodies. Testing for genetic mutations can also help detect cancer.
There are several types of treatment for cancer. Sometimes surgery is effective all by itself, if it is possible to remove the whole tumor. Surgery is usually either preceded or followed by radiation which causes cell cycle disruption. Chemotherapy is a very common treatment which treats the whole body. This treatment interferes with DNA synthesis. There are also quite a few new therapies that are currently in clinical trials. One of the new ideas is to use immune cells that have been genetically engineered to beat the tumor antigens. Another proposed therapy is drugs that inhibit angiogenesis which confine and reduce tumors.
Genetics and the genes we inherit from our relatives play a big part in making us who we are. Genotype are the genes of an individual. Different forms of a gene that have the same position, or locus, on a pair of chromosomes that affect the same trait are called alleles. A dominant allele uses an uppercase letter and a recessive allele uses a lowercase one. If a zygote has a homozygous dominant genotype, that means it would be denoted by using two uppercase letters, such as EE. A homozygous recessive would possibly be ee, and a heterozygous dominant would use one of each, or Ee. A phenotype is the physical appearance of a person. Either a homozygous dominant or a heterozygous dominant would result in the person having the dominant phenotype.
The chromosome number is reduced during the process of gametogenesis. If an individual had the alleles EE, all gametes would have an E. If an individual were Ee, half would carry and E, and the other half an e. If all were ee, the all the gametes would have an e.
A punnett square illustrates when all possible types of sperm are lined up vertically and all possible types of eggs are lined up horizontally. The result is that all possible combination of gametes is shown. This allows you to figure the chances of an individual having certain genotypes or phenotypes.
If a genetic disorder is autosomal dominant, any individual with alleles AA or Aa will end up with the disorder. If the disorder is autosomal recessive, only individuals with aa will have the disorder. It is possible for parents to be carriers and pass a disorder onto their child without actually having the disorder themselves. In reverse, the parents can each have a disorder without passing it on to their child.
One well known autosomal disorders is Tay-Sachs disease, which occurs commonly among Jewish people in the United States. A baby is born appearing to be healthy. Between four and eight months old the child's development slows down and neurological impairment and psychomotor difficulties begin. The child becomes blind and helpless, begins to have seizures, and ends up paralyzed. Another autosomal recessive disorder is Cystic fibrosis which is most lethal in american caucasians. Mucus in the bronchial tubes is very thick interfering with breathing. Huntington disease is a neurological disorder that included progressive degeneration of the cells in the brain. People with this condition deteriorate quickly. I have a client with this disorder that, in the last three years, I have seen the rapid progression, and it is very sad to watch.
There are several other type of inheritance patterns. Skin color and height are regulated by multiple sets of alleles. These are called polygenic traits. Environmental influences contribute to polygenes that cause club foot, schizophrenia, and cleft lip. Blood type is controlled by multiple alleles.
Traits controlled by the genes in the sex chromosomes are considered sex linked. Color blindness is an example of an x-linked trait. Most sex linked disorders are usually on the x chromosome. Muscular dystrophy, and hemophilia are common X linked disorders.
DNA is found mainly in the chromosomes and is our genetic material. Any genetic material has to be able to replicate to transmit to the next generation, store information, and undergo mutations that provide genetic variability. DNA is considered a double helix in shape, made up of two strands that twist around each other. The individual strands are known as polynucleotides. The bases are held together by hydrogen bonds. A pairs with T, and G pairs with C. DNA replication happens when cells divide and each new cell that results gets an exact copy of the DNA. It is rare for a replication error to occur. Normally, if an error does occur, repair enzymes fix it. However, if it persists, it is called a mutation, and permanently changes the sequence of bases. This can cause a change in the phenotype and is what makes everyone different.
RNA is made up of nucleotides that contain ribose. Instead of containing the base thymine, RNA contains uracil. RNA is single stranded. There are three types of RNA. Ribosomal RNA (rRNA) is where proteins are synthesized. Messenger RNA (mRNA) carries genetic information from the DNA to the ribosomes. Transfer RNA (tRNA) transfers amino acids to the ribosomes.
Proteins are made up of amino acids. They determine the function and the structure of all the cells in our body. The protein hemoglobin is what causes our red blood cells to be red in color.
Gene expression is how the four bases can provide enough combinations to code for 20 amino acids. There are several steps to this process. Transcription is the first phase. First, mRNA is formed and then it has to be processed before it can enter the cytoplasm. The next phase is translation. During this phase, tRNA molecules bring amino acids to ribosomes. There polypeptide synthesis occurs following the steps : initiation, elongation, and termination. DNA contains a triplet code which stands for a specific amino acid. The chromosome in a certain region must decondense in order for a gene to be transcribed in human cells.
During a thirteen year effort, the Human Genome Project figured out the order of the three billion bases A, T, C, and G in our genomes. The investigators deciphered a short sequence of base pairs using sperm DNA. Genome size is suprisingly not proportionate to the number of genes and does not have anything to do with the complexity of the organism. Then the HGP found out how our gene function in cells to create a human being. By comparing genomes, we are able to better understand how species have evolved. The genomes of all vertebrates are remarkably similar. New endeavors in the scientific world include proteomics (the study of the structure, function, and interaction of cellular proteins), and bioinformatics (the application of computer technologies to the study of the genome).
A person's genome can be modified through Ex vivo gene therapy or in vivo gene therapy.
Science now allows us to clone genes. "Cloning is the production of genetically identical copies of DNA, cells, or organisms through an asexual means (Mader, pg458)." Recombinant DNA allows genes to be cloned. A technician needs a vector where the gene of interest will be introduced into a host cell. Plasmids are common uses for vectors.
Biotechnolgy products include bacteria, plants, and animals which have been genetically engineered. Certain genes are introduced into the cells of these living organisms to get them to behave and develop in certain ways. Animal organs can be used instead of human organs in transplant patients.

In addition to the textbook, I used the following sources:

http://www.mun.ca/biology/scarr/F14-10_FISH_chromosome.jpg

http://nobelprize.org/nobel_prizes/medicine/laureates/2001/cellcycle_eng.jpg

http://www.dartmouth.edu/~cbbc/courses/bio4/bio4-lectures/images/mitosis.JPG

http://faculty.uca.edu/~johnc/meiosis.jpg

http://www.newscentre.bham.ac.uk/images/Dividing_Cancer_Cell-small.jpg

http://celebritygeckos.com/Portals/28/Genetics/Genetics/basicpunnetsquare.JPG

http://fig.cox.miami.edu/~cmallery/150/gene/c7.17.7b.transcription.jpg

http://cache.eb.com/eb/image?id=73582&rendTypeId=35

Genetics Lab

2008-09-13T13:51:00.000-07:00

Example of a Punnet square for 2 heterozygous genotypes

NOTE - there might be some missing images...for

some reason my computer and adding images to this blog just wasn't working...I lost my whole blog post at one time and had to redo it all

I, personally, found Chapter 20, "Patterns of Genetic Inheritance", to be the most interesting so far. I can remember enjoying this part of biology back in 9th grade, but that was a good fifteen years ago. Genetics basically is what defines who we are. Our parents, our grandparents, and ancestors before them have passed down their genetic information to us to help make us who we are. It can be anything from the color of our eyes, to, unfortunately, being more susceptible to a disease. Once again, I couldn't get my computer to cooperate with copying the whole screen, so I again have images from my digital camera.l'd like to define some basic genetic terms.

final screen from fruit fly punnett square

Both parents were heterozygous dominant (meaning they carried one dominant and one recessive gene which presents as a dominant trait)

Genotype is the genes that an individual has. The following Punnet square shows the genotype of a pollen (Bb), crossing with a pistil (also Bb)

Phenotype is the visual characteristic that an individual has. Here, I am going to seize the opportunity of showing off my daughter by using the illustration that red hair is a phenotype.

An allele is the alternative forms of a gene that have the same position on a pair of chromosomes and affect the same trait.

A cross is what you get when you combine the genes of both parents and come up with the characteristics of the offspring. (final screen of dragon genetics...all genes were matched up...I actually had a hard time matching the color until I realized you could look up what the genotype was supposed to be)

An example of genotype in this lab would be the gene for color 2 Bb, and the phenotype would be the dragon's blue skin.

A dominant allele is expressed by the use of a capital letter, and has a higher chance of being passed on as does a recessive. For example, the genotypes EE, and Ee would both show the dominant trait.

A recessive allele is expressed by the use of a lowercase letter, and when mixed with a dominant, the dominant trait will show. Only the genotype ee would show the recessive trait.

Once again, genetics makes up most of who we are. We inherit many things from our ancestors from red hair to anemia.

http://users.adelphia.net/~lubehawk/BioHELP!/psques3b.jpg

Compendium Review Unit 1 Major Topic 1

2008-09-10T20:06:00.000-07:00

Compendium Review Chapters 1-4
I.Exploring life and Science
A.Characteristics of Life
B.How humans are related to Other Animals
C.Seeing Science as a Process
D.Understanding Scientific Study
II.Chemistry of Life
A.From Atoms to Molecules
B.Water and other Living Things
C.Molecules of Life
1.carbohydrates
2.lipids
3.proteins
4.nucleic acids
III. Cell Structure and Function
A.What is a cell?
B.How are cells organized?
C.Parts of a cell
1.plasma membrane
2. nucleus
3.ribosomes
4.endoplasmic reticulum
5.Golgi apparatus
6.lysosomes
D.Cytoskeleton and Cell Movement
E.Mitochondria and Cellular Metabolism
IV. Organization and Regulation of Body Systems
A.Types of Tissues
1.connective
2.muscular
3.nervous
4.epithelial
B.Cell Junctions
C.Skin
D.Organ Systems
E.Homeostasis
Life has seven basic characteristics. Life is organized, from atoms to the biosphere. Ranging from smallest to largest there is the atom, followed by molecule, cell, tissue, organ, organ system, organism, population, community, ecosystem, and biosphere. All living things take materials and energy from the environment. Humans and animals acquire energy through the consumption of food. Most living things convert energy into motion. All living things reproduce, creating a copy of the parents. The genes in DNA molecules pass on hereditary info. All living things grow and develop, increasing in size and the number of cells. Living things also share the quality of being homeostatic. Organ systems maintain homeostasis in living things. “For example, human body temperature normally fluctuates slightly between 36.5 degrees Celsius and 37.5 degrees Celsius (Mader, pg. 4)” All living things also respond to stimuli. This can even be noticed in plants which will lean toward their source of light. Finally, all living things have an evolutionary history. Species have changed throughout time to adapt to their environment.
Humans are related to other animals. There are three domains of life.

Archae and bacteria both lack a nucleus. The third domain, is the eukarya, which have a nucleus and are divided into 4 kingdoms : protista (with approximately 250, 000 species), fungi (100,000 species), plantae (250,000 species), and animalia (1,000,000 species). Humans, of course, belong to the kingdom animalia. All humans have a cultural heritage. Activities and products pass on through generations. Humans are important members of the biosphere, but also pose a threat to it as well
Science has a very defined process. Scientists use a method called the scientific method to come up with scientific theories.

The steps to the scientific method are as follows :
1.observation – the researcher makes an observation about a process or event
2.hypothesis – the researcher formulates an idea as to what will happen when a certain situation occurs
3.experiment and observations – the researcher tests the hypotheses
4.conclusion – the researcher comes to a conclusion based on results of the experiment and observations
5.scientific theory – if there is enough evidence to support it, the reasearcher’s discovery becomes a scientific theory
We often use the scientific method to discover things on our own, without even realizing it. For example, when I was reading this chapter more than a week ago, I noticed my not quite 2 year old daughter using it to make a discovery. Here is how she used it.
1.observation – She was sitting on her potty chair, and I was standing in the bathroom with her. She covered her eyes, and remarked, “It’s dark.”
2. hypothesis - She then decided in her mind that when it’s dark she can’t see things.
3. experiment - She sat there for a solid five minutes covering her eyes saying, “It’s dark…no see mama”, then uncovering her eyes saying , “it’s bright – oh, there mama is”. She did this repeatedly (a good scientist always conducts their experiment more than once).
4.conclusion – after five minutes of this repeated behavior, she proudly announced “When cover eyes, it’s dark. I no see mama.”
Experiments are often done by performing a controlled study. In a controlled study, the only things that change are the experimental variables. For example, when testing the effectiveness of a medicine, the control group are just given a placebo. The test group are given the actual medicine. In a completely objective study, a double blind experiment is performed where neither the patient or the examiner know which group is given what.
Scientific journals are highly regarded as the most trustworthy source of scientific information. They come straight from the researcher instead of being passed on by a third, or even fourth, party. They go through a thorough review process before being published. If you look to the internet for scientific information, your best bet are sites ending in .edu, .gov, and .org.
Elements are a basic building block of nature. There are 92 known elements. They are known by name and symbol. For example, Oxygen is O, and Iron is Fe.
Atoms are the smallest unit of life. They have protons, which have a positive charge, and neutrons, which are neutral, in the nucleus. Electrons, with a negative charge, orbit in rings around the nucleus. All elements have an atomic number which tells how many protons and electrons that element has. The atomic mass is equal to the number of neutrons.
Isotopes differ in mass from the original element. Some of these can be radioactive, and are called radioisotopes. If they are used in low levels, they can be used as tracers to be injected into the body to help doctors find what is wrong with organs and tissues. In high levels, radiation can harm cells, damage DNA, or even cause cancer. Scientists have been able,
however, to control the radiation, and have it “introduced into the body in a way that allows radiation to destroy only cancer cells, with little risk to the rest of the body (Mader, og.21a).”
Atoms bond together to form molecules. If the atoms that bond together are different, they form something called a compound. There are two main types of bonding that can occur. These are ionic and covalent. In ionic bonding, atoms give up or take on electrons as they bond to one another. In covalent bonding, the atoms share electrons.
Water is the most abundant thing found in living organisms. It makes up 60 to 70% of total body weight. Water is formed by hydrogen bonds which occur when a covalently bonded hydrogen is only slightly positive and attracts to a negative atom some distance away.
There are six important properties of water. Water is a liquid when it is at room temperature. This gives it several uses, such as drinking, cooking, and bathing. The temperature of water when it is in liquid form, rises and falls very slowly in order to prevent sudden changes. Water keeps the body form overheating because it has a high heat of vaporization. Frozen water is less dense than liquid water, which allows for ice to float on water. This is why aquatic animals have a better chance of surviving cold weather – the ice forms on the surface of the water, allowing them to move freely in the slightly warmer water underneath. Water molecules are cohesive which allows liquids to fill vessels. Water is a solvent for polar molecules and allows chemical reactions to occur. “Ions and molecules that interact with water are said to be hydrophilic. Nonionized and nonpolar molecules that do not interact with water are said to be hydrophobic (Mader, pg25).”
Acids have a high number of hydrogen ions. Some acids that are most commonly known are lemon juice, and coffee. Bases have a low number of hydrogen ions. The most commonly known of these are milk of magnesia, and ammonia. Acids and bases are measured according to the pH scale which is a system of numbers, 0 being the most acidic and 14 being the most basic. 7 is neutral, and includes pure water and tears.

pH scale

There are four molecules of life. These are carbohydrates, lipids, proteins, and nucleic acids. Carbohydrate molecules look like this : H-C-OH. There are monosaccharides and disaccharides which are considered simple carbs These are when the number of carbon atoms in a carbohydrate are low. Complex carbohydrates, or polysachharides, include starch, glycogen, and cellulose. High fiber carbohydrates can be beneficial to the diet. Lipids are most commonly known as fats, which come from animals, and oils, which come from plants. Emulsifiers can cause fats to mix with waters. Saturated fats have no double bonds between the carbon atoms. Unsaturated fats have double bonds between the carbon atoms. Trans-fats are partially hydrogenated which means that not all bonds are saturated with hydrogen molecules. Steroids are a special type of lipid that differ greatly in structure from fats. Proteins serve many important functions in humans. Proteins such as keratin and collagen provide structural support. They produce enzymes which speed chemical reactions in cells. Channel and carrier proteins exist in the plasma membrane and allow substances to enter and exit the cells. Antibodies are a special type of protein that provide defense. Hormones are a type of regulatory protein. Actin and myosin are contractile proteins that cause muscle contraction, allowing movement. Protein structures have at least three levels of structure…the primary which is linear, the secondary which is an alpha helix or a pleated sheet, and the tertiary, which is three dimensional. Some also have a fourth level, or quaternary structure. There are two types of nucleic acids. These are DNA and RNA. DNA molecules contain many genes which specify the sequence of amino acids. The structure of DNA and RNA differ in their nucleotides. DNA contains the sugar deoxyribose and RNA contains ribose. There are four types of bases in DNA - adenine, thymine, guanine, and cytosine. In RNA, the base uracil replaces thymine. ATP, or adenosine triphosphate , is an energy carrier in cells

animal cell

The cell theory states that a cell is the basic unit of life and that all living things are made up of cells. It is also known that new cells arise only from preexisting cells. Cells have an evolutionary history. Prokaryotic cells, which had no nucleus, were the first cells. Eukaryotic cells evolved from archaea and have a nucleus, and also an endomembrane system. Eukaryotic cells also have a plasma membrane, cytoplasm, and organelles. The plasma membrane is a phospholipid bilayer which is liquid at room temperature. Its main function is to keep cells intact. It is selectively permeable, which means that it only allows certain substances to pass through. There are several ways in which substances are able to cross the plasma membrane. Diffusion is one of them. It is the random movement of molecules from an area of higher concentration to an area of lower concentration. Osmosis is the diffusion of water across a plasma membrane. The three types of osmosis are isotonic, hypotonic, and hypertonic. In facilitated transport, molecules are transported at a higher rate. In acttive transport, molecules move contrary to normal. "During endocytosis, a portion of the plasma membrane invaginates, or forms a pouch, to envelop a substance and fluid. (Mader, p.48)" Exocytosis occurs as a vesicle fuses with the plasma membrane.
The nucleus is the core of the cell. It stores the genetic info and contains DNA and RNA. It also has chromatin which contains DNA and protein. The nucleus is separated from cytoplasm by a nuclear envelope and endoplasmic reticulum. The ribosomes house the protein and rRNA. The endomembrane system is composed of several parts. There is both smooth and rough endoplasmic reticulum, the golgi apparatus, and the lysosomes. The cytoskeleton is made up of large microtubules. It helps maintain a cell's shape and either anchors the organelles or

assists their movement. Organelles move either by cilia or flagella.
Mitochondria are the powerhouses of the cell. The process of producing ATP is known as cellular respiration. Respiration is a component of metabolism. Enzymes speed up chemical reactions and coenzymes are nonprotein molecules that assist the activity of an enzyme. After glucose and oxygen are transported to cells by the blood, cellular respiration occurs. The main function of cellular respiration is to break down glucose to carbon dioxide and water. The three pathways involved in the breakdown of glucose are glycolysis, which literally means sugar splitting, citric acid cycle, which completes the break down of glucose, and the electron transport chain which accepts two electrons and passes them on to the next carrier, Fermentation is an anaerobic process which gives the body a short energy boost. However, it promotes the buildup of lactate which is toxic to cells and causes muscle cramps and fatigue.
There are four main types of tissues : connective, muscular, nervous, and epithelial.

Four types of tissue

Connective tissues by themselves, have several different types...all with the main function of connecitng and supporting. Fibers are one type of connective tissues and these include collagen, reticular, and elastic. Fibrous connective tissue ca be loose, adipose, or dense (found in tendons and ligaments). Supportive connective tissue is cartiage and can be hyaline (found in the nose), elastic (outer ear), and fibrocartiilage (disks). Bone is also a type of connective tissue and can be compact or spongy. Many people would not think of blood as a tissue, but it is known as a fluid connective tissue, as is lymph. Muscular tissues include skeletal (which is voluntary), smooth (visceral), and cardiac (found in the heart). Nervous tissue communicates and consists fo nerve cells called neurons and neuroglia. Epithelial tissue protects. Simple epithelial tissue can be squamous, cuboidal, or columnar. Pseudostratified columnar appears to be layered. In transitional epithelial tissue, tissue changes in response to tension. Stratified epithelia have many layers of cells piled on top of one another. Glandular epithelia secretes a product. There are three types of cell junctions which help a tissue perform its particular function : tight, adhesion, and gap. The skin of our bodies is known as our integumentary system. It's regions include the epidermis, and the dermis. The subcutaneous layer is beneath the dermis and is not considered a part of skin. It is a common site for injections. There are several parts of our body that are considered accessory organs of the skin. These include nails, hair follicles, oil glands, and sweat glands.
There are many other organ systems in our body that are not delved into in Chapter 4. These include the cardiovascular, the lymphatic and immune, the digestive, the respiratory, the urinary, the skeletal, the muscular, the nervous, the endocrine, and the reproductive.
Homeostasis helps to maintain relative constancy of the internal environment by adjusting physiological processes. Negative feedback keeps the variable close to a set point. Positive feedback brings about an ever greater change.

Aside from using the textbook for this information I also used the following websites
http://waynesword.palomar.edu/trfeb98.htm
http://scienceblogs.com/clock/2007/01/current_biological_diversity.php
http://images.google.com/imgres?imgurl=http://www.indiana.edu/~geol116/week1/meth%2520copy.jpg&imgrefurl=http://www.indiana.edu/~geol116/week1/week1.html&h=900&w=2100&sz=296&hl=en&start=13&sig2=TCF4zoZl1cLrAmHZogAnOA&um=1&usg=__Yl66ldyeT1sp9eXodRWSTEPmpDw=&tbnid=ShhXAxm-MA41qM:&tbnh=64&tbnw=150&ei=nEvHSNjqHo6OsQOYj7HUDw&prev=/images%3Fq%3Dscientific%2Bmethod%26um%3D1%26hl%3Den%26sa%3DN
http://upload.wikimedia.org/wikipedia/commons/thumb/4/46/PH_scale.png/639px-PH_scale.png
http://www.uvm.edu/~inquiryb/webquest/fa06/mvogenbe/Animal-Cell.jpg
http://apps.uwhealth.org/health/adam/graphics/images/en/8682.jpg

Microscope Lab

2008-09-07T13:21:00.000-07:00

The lab was fun, but my computer did not want to cooperate with saving the whole screen. I took pictures of the screen with the flash turned off on my digital camera...I hope those will suffice.

First off, let's start with the history of the microscope. The first one was created by Zacharias Janssen (possibly begun by his father) in Holland in 1595. The first compound light microscope was just a simple tube with lenses at either end. It magnified from 3x to 9x. Robert Hooke improved on the microscope around 1660. He coined the word cell to describe features of the plant tissue he had seen under the microscope. The Egyptians, however, may have had an idea of some of the concept for what would become the microscope. There were rock crystal artifacts in the shape of convex leses discovered from around 2600 BCE. Max Knoll and Ernst Rusta invented the first electron microscope in 1931 CE.

There are four main types of microscopes. The most commonly used one is the compound light microscope. It is light illuminated and provides a 2 dimensional view of the specimen. It allows the viewer to see individual cells, including live ones. It has a high magnification, but low resolution. Then there is the dissection microscope whic is also light illuminated. It provides a 3 dimensional image. It does not allow the viewer to see individual cells as it has a low magnification power. Another type is the scanning electron microscope whic is electron illuminated. This provides a 3 dimensional image and has both high magnification and high resolution. The specimen has to be coated in gold, and it produces a black and white image. The final type of microscope is the transmission electron microscope, also electron illuminated. It produces a 2 dimensinal image and uses thin slices of the specimen. It also has both high magnification and high resolution.

Here are the slides I viewed during the lab

onion root tip at 40X

bacterial capsule at 40X

cheek smear at 40X

The parts of a microscope are used as follows:

STAGE - this is the platform where you set your slide for viewing. It is easiest adjusted looking at the microscope. You want to lower it to place your slide, then move it to its top position before viewing.

FOCUS KNOBS - There are two of these, located on the side of the microscope, both best adjusted while looking through the microscope. The coarse focus knob adjusts very quickly and the fine focus fine tunes the image and adjusts slowly.

IRIS - the iris controls the amount of light let through to view the specimen. It is located under the stage and is best adjusted while looking through the microscope.

OCULARS - These are the pieces you look through. They need to be adjusted to fit your face. The usual starting position is both of them on 64. You need to look through them to see if they are adjusted properly. It is best to look through these with your eyes 3/4 of an inch above them.

OBJECTIVES- these are the lenses that magnify your specimen. There are usually 4 on a compound light microscope. You always want to start with the 4X objective and then adust upwards. These are best adjusted looking at the microscope.

Introductory Post

2008-08-23T13:32:00.001-07:00

Hello, fellow students, my name is Erin Sink.

My favorite artist is painter Georgia O'Keefe...I studied her in an art class in fourth grade, and have alway been intrigued by her paintings of flowers.

I am taking this class because I am trying to finish my associates degree and then join the nursing program. I graduated highschoolin 1996, attended a year and a half of college, and then due to circumstances beyond my control, am just now able to finish my last semester one class at a time.

I hope to achieve a better understanding of human biology, and it looks like this will be an enjoyable class. For some reason, I always excelled in math, reading, and english, but had difficulty with the sciences. Hopefully, as this is my only class, I will be able to excel.

Three interesting things:

1. I have a beautiful redheaded daughter that will be 2 in October who functions at a 3 and a half year old level : she speaks in full sentences, never forgets a name, is potty trained, knows all her colors, shapes, abcs, and numbers, counts in 3 languages, does gymnastics, and even reads a few words.

2. My husband and I met on an online dating site and just celebrated our 5th anniversary last week!

3. My passion is working with people, children especially, with developmental disabilities, and I have done this since I was 12 (I'm 29 now).