REGARDING YOUR OWN PERFORMANCE
1. What were the three aspects of the assignments I've submitted that I am most proud of?
I enjoyed the big lab about what i encounter each day. I felt strongly opinionated in my essay. And i also enjoyed doing the population lab.
2. What two aspects of my submitted assignments do I believe could have used some improvement?
I actually felt very strongly this time in everything...but i bet everything could use something to make it better...whether it be better wording, more pictures, etc.
3. What do I believe my overall grade should be for this unit?
I feel i did quite well, mostly compared to when we first started. I would hope for a B at least.
4. How could I perform better in the next unit?
There are no more *gasp!*
REGARDING THE UNIT (adapted from Stephen Brookfield, University of St. Thomas "Critical Incident Questionnaire")
At what moment during this unit did you feel most engaged with the course?
I think when learning about the developing fetus...mostly because i have a friend who is due in July and i why was trying to imagine what was going on inside of her!!
At what moment unit did you feel most distanced from the course?
Probably when learning about evolution...it jsut doesn't catch my interest the way the human body itself does
What action that anyone (teacher or student) took during this unit that find most affirming and helpful?
Again, i always always always appreciate the emails pushing us along.
What action that anyone (teacher or student) took during this unit did you find most puzzling or confusing?
Nothing that i can recall.
What about this unit surprised you the most? (This could be something about your own reactions to the course, something that someone did, or anything else that occurs to you.)
I think how much i enjoyed it suprised me. I guess my interest in anatomy and how the body works and the fact that my friend is pregant made a lot of this unit more at home and interesting to me than all the others. I think this unit was my favorite!
Monday, May 12, 2008
overpopulation---i am opinionated---i apologize.
I have always heard that we were overpopulated, not only as a country, but in the world. And while I may be joking, I part of me is always serious when I say “people need to stop having so many babies.” Yes it might sound a little bit Hitler-ish, but if people in other countries, and our own, are starving, why would we want even more people to add to this problem?
I think one of the biggest problems regarding overpopulation is that people in underdeveloped countries are at a disadvantage. They do not always know about contraceptives and how to prevent pregnancy, and each birth in some of these countries just means another hungry human had to suffer. And I am not trying to put any blame on these people for what they do not know, I just feel others that are educated have a duty to teach what they know.
Regarding the United States and other developed, overpopulated countries…I do lay some blame. Why do we have to have so many children? Why are we not using contraceptive? And if they are something someone is against because of their religion, why are we not being more careful? I do feel it is a blessing to have a child, but think of all the children in the world that need homes. Why don’t we help them before fulfilling our “need” to give birth to our “own” child? It is something I will never understand, but I feel very strongly about. Mostly in the cases of people who cannot have children. I understand we have the technology to make pregnancy possible, but why is it necessary? A child that isn’t living in such an overpopulated world that they cannot eat, cannot get a job, cannot do all of the things that you or your parents may have done, is not necessarily going to be the happiest adult….just an opinion but one I feel strongly about.
I just feel that if we can educate other countries and ourselves on the issues of contraceptives, overpopulation, etc, we may finally see less of an increase each year. Too many people are suffering from this problem.
I think one of the biggest problems regarding overpopulation is that people in underdeveloped countries are at a disadvantage. They do not always know about contraceptives and how to prevent pregnancy, and each birth in some of these countries just means another hungry human had to suffer. And I am not trying to put any blame on these people for what they do not know, I just feel others that are educated have a duty to teach what they know.
Regarding the United States and other developed, overpopulated countries…I do lay some blame. Why do we have to have so many children? Why are we not using contraceptive? And if they are something someone is against because of their religion, why are we not being more careful? I do feel it is a blessing to have a child, but think of all the children in the world that need homes. Why don’t we help them before fulfilling our “need” to give birth to our “own” child? It is something I will never understand, but I feel very strongly about. Mostly in the cases of people who cannot have children. I understand we have the technology to make pregnancy possible, but why is it necessary? A child that isn’t living in such an overpopulated world that they cannot eat, cannot get a job, cannot do all of the things that you or your parents may have done, is not necessarily going to be the happiest adult….just an opinion but one I feel strongly about.
I just feel that if we can educate other countries and ourselves on the issues of contraceptives, overpopulation, etc, we may finally see less of an increase each year. Too many people are suffering from this problem.
population lab
1)What was your high fertility rate country and what was its fertility rate?
My high fertility rate country was China with a fertility rate of 2.37 children. The population in 2050 is at a horrible high 1,759,855,000 people. All i ever hear about is how crowded china is, therefore, i thought it would be perfect for my high population.
2)What was your low fertility rate country and what was its fertility rate?
My low fertility rate country was Luxembourg with a fertility rate of 1.59 children. The population in 2050 is at 516,053 people. I actually chose Luxembourg because my maternal grandfather has family still in Luxembourg at this day in time. I heard it's beautiful and I assumed it's because it's not a very big country.
3)The initial demographic "shape" of your high fertility rate country should have been a pyramid, with high population in young age groups. Explain why high fertility rate results in a high percentage of young people in the population. How does this affect future population growth?
Though China is in a pyramid shape, the pyramid is not very drastic. There are probably more opportunities at birth and in childhood for people to keep themselves healthy, therefore, i think that would keep them living longer. China though is a very booming country and i think that because of what kind of health care is available now in developed countries, such as cancer treatments, that would explain why the pyramid still is wide at the top because more people are living to be older.
4)Your low fertility rate country might have had a more oval-shaped curve with high population in middle age groups. This is especially exaggerated if the fertility rate is below 2.00. Explain why low fertility rate leads to lots of middle-aged people.
I think that the fertility rate is lower simply because people wait to have children. In general, the population is so much smaller than china it's hard to compare. But if people are waiting, this would explain why there are more of one age than any other.
5)Write ten adjectives or descriptive phrases for what you might expect life, people's attitudes, conditions on the streets, etc. will be like in each of those situations. Imagine a situation with lots of middle-aged and older people in the population and write ten quick "brain-storm" descriptors for you think it would be like (Prescott, Arizona?). Then do the same for a situation with lots of children in the population.
Middle Aged:
Educated, Independent, Responsible, Successful, Having fun, Working, Mature, Living life, Less violence, Happiness
Lots of Children:
More crime, Less Education, "bored" fun, Not enough jobs, Less income, More broken homes, More wild fun, Disobeidience, Working instead of school, Older/less taken care of communities
I have concluded that because Luxembourg is smaller and less busy, the population will always remain at a more managable rate. It seems that it is one of those countries that is in no need to expand uncontrollably. This makes it seem like it would be a safer place to live and a better experience all around...that is unless you love a big crowd all the time.
fetal development.
The ten significant developments that I chose are listed below. I honestly had a hard time choosing just ten, so it does jump a lot, but I feel there was really no wrong stage to list.
1) One day post ovulation.
*I feel this is the most important day of the development because it is the time of the fertilization. Skip this step and we’ve hit a dead end. It takes about 24 hours for the whole process to take place, but once it does, the development begins.
2) Seven to ten days post ovulation.
*This is the time period in which the implantation of the fertilized egg is complete. After this happens, the egg can begin the growing process.
1) One day post ovulation.
*I feel this is the most important day of the development because it is the time of the fertilization. Skip this step and we’ve hit a dead end. It takes about 24 hours for the whole process to take place, but once it does, the development begins.
2) Seven to ten days post ovulation.
*This is the time period in which the implantation of the fertilized egg is complete. After this happens, the egg can begin the growing process.
3) Thirteen days post ovulation.
*This is when the placenta forms. This is very important because during the nine months of pregnancy, the placenta feeds and nourishes the fetus while also getting rid of toxins.
4) Twenty one to twenty three days post ovulation.
*This is when the neural and heart folds begin to fuse. This is obviously important in the further development later on of the heart, brain, etc.
*This is when the placenta forms. This is very important because during the nine months of pregnancy, the placenta feeds and nourishes the fetus while also getting rid of toxins.
4) Twenty one to twenty three days post ovulation.
*This is when the neural and heart folds begin to fuse. This is obviously important in the further development later on of the heart, brain, etc.
5) Twenty six to thirty days post ovulation.
*This is when the skin starts to form. While it is only a thin layer, it is already working to protect the body. The limbs have slowly started to bud, so development happens quite quickly. This stage is very important to protect the body during this development.
6) Basic brain structure is in place.
*There is a massive increase in the brain structure. The teeth are beginning to form. The intestines are now in the abdomen. The thyroid is now producing insulin.
7) Fourteen weeks post fertilization.
*The sex of the baby is now visible. The muscles are straightening and the body is growing. The heart is pumping a little faster.
*This is when the skin starts to form. While it is only a thin layer, it is already working to protect the body. The limbs have slowly started to bud, so development happens quite quickly. This stage is very important to protect the body during this development.
6) Basic brain structure is in place.
*There is a massive increase in the brain structure. The teeth are beginning to form. The intestines are now in the abdomen. The thyroid is now producing insulin.
7) Fourteen weeks post fertilization.
*The sex of the baby is now visible. The muscles are straightening and the body is growing. The heart is pumping a little faster.
8) Twenty weeks post fertilization.
*The bone marrow starts making blood cells. Now the heart is beginning to beat stronger and faster. The limbs are most likely done growing. The fetus is starting to take in small amounts of sugar.
9) Twenty four weeks post fertilization.
*This is when sensory brain waves activate. The eyes and ears begin to respond to stimulation now. The baby’s fingers/toes are still continuously growing. The spine is beginning to become more supportive.
*The bone marrow starts making blood cells. Now the heart is beginning to beat stronger and faster. The limbs are most likely done growing. The fetus is starting to take in small amounts of sugar.
9) Twenty four weeks post fertilization.
*This is when sensory brain waves activate. The eyes and ears begin to respond to stimulation now. The baby’s fingers/toes are still continuously growing. The spine is beginning to become more supportive.
10) Forty weeks post fertilization.
*The fetus is at full term. The organs should all be developed and working properly. The nervous system should be working. Everything that will keep the baby healthy should be ready to go. The baby is turned upside down and ready to be born.
*The fetus is at full term. The organs should all be developed and working properly. The nervous system should be working. Everything that will keep the baby healthy should be ready to go. The baby is turned upside down and ready to be born.
species interactions
Common name: My boyfriend....i have a real one...this one is imaginary :)
Scientific name: Homo Sapiens
Ecological principles: Symbiotic. Domesticated. Human beings interact with one another every day. We basically need each other for survival.
Common name: Harley, English Bulldog
Scientific name: canis Lupus Familiaris
Ecological principles: Symbiotic, domesticated. Now have become pets over evolutionary time.
Common name: Soy milk
Scientific name: Glycine Max
Ecological principles: Commensal and domesticated because we use it as food.
Common name: Duck
Scientific name: Anas rubripes
Ecological principles: Commensal and non domesticated because we do not usually have ducks as pets.
Common name: Pigeons
Scientific name: Colomba ssp.
Ecological principles: Commensal and non domesticated. We do not usually have pigeons as pets.
Common name: Fleas
Scientific name: Ctenocephalides canis
Ecological principles: Non domesticated. We do not want them around!
Common name: Banana
Scientific name: Musa X paradisiaca L.
Ecological principle: Commensal. Domesticated. We use it for food.
Common name: Fish (minnow)
Scientific name: Pimephales notatus
Ecological principles: Commensal and non domesticated because they are not usually pets or food. Other fish may be domesticated because they are used for food.
Common name: Crow
Scientific name: Corvus brachyrhynchos
Ecological principles: Non domesticated. Commensal. We do not usually have a crow for pets.
Common name: facial bacteria
Scientific name: Hafnia
Ecological principles: non domesticated, we do not use them voluntarily or want them.
Scientific name: Homo Sapiens
Ecological principles: Symbiotic. Domesticated. Human beings interact with one another every day. We basically need each other for survival.
Common name: Harley, English Bulldog
Scientific name: canis Lupus Familiaris
Ecological principles: Symbiotic, domesticated. Now have become pets over evolutionary time.
Common name: Broccoli
Scientific name: Brassica oleracea var. botrytis
Ecological principles: Commensal. Domesticated. We use it as food.
Scientific name: Brassica oleracea var. botrytis
Ecological principles: Commensal. Domesticated. We use it as food.
Common name: Grass
Scientific name: Setaria viridis
Ecological principles: Commensal. A type of domesticated plant.
Scientific name: Setaria viridis
Ecological principles: Commensal. A type of domesticated plant.
Common name: Milk—from a dairy cow
Scientific name: Bos Taurus
Ecological principles: Commensal. Domesticated because we use it as food.
Scientific name: Bos Taurus
Ecological principles: Commensal. Domesticated because we use it as food.
Common name: Soy milk
Scientific name: Glycine Max
Ecological principles: Commensal and domesticated because we use it as food.
Common name: Duck
Scientific name: Anas rubripes
Ecological principles: Commensal and non domesticated because we do not usually have ducks as pets.
Common name: Pigeons
Scientific name: Colomba ssp.
Ecological principles: Commensal and non domesticated. We do not usually have pigeons as pets.
Common name: Fleas
Scientific name: Ctenocephalides canis
Ecological principles: Non domesticated. We do not want them around!
Common name: Butter
Scientific name: anhydrous stannic chloride
Ecological principles: Commensal and domesticated because we use it for food.
Scientific name: anhydrous stannic chloride
Ecological principles: Commensal and domesticated because we use it for food.
Common name: Banana
Scientific name: Musa X paradisiaca L.
Ecological principle: Commensal. Domesticated. We use it for food.
Common name: Intestinal Bacteria
Scientific name: Shigella
Ecological principles: Non domesticated. We do not use it voluntarily...or want it.
Common name: Tea
Scientific name: Camellia sinensis
Ecological principles: Commensal. This is considered a domesticated species because we use it for food/ drink.
Scientific name: Shigella
Ecological principles: Non domesticated. We do not use it voluntarily...or want it.
Common name: Tea
Scientific name: Camellia sinensis
Ecological principles: Commensal. This is considered a domesticated species because we use it for food/ drink.
Common name: Bluebonnets
Scientific name: Lupinus texensis
Ecological principles: Commensal. A type of domesticated plant.
Scientific name: Lupinus texensis
Ecological principles: Commensal. A type of domesticated plant.
Common name: Mosquitoes
Scientific name: Anopheles
Ecological principles: Non domesticated because we do not use them/want them.
Scientific name: Anopheles
Ecological principles: Non domesticated because we do not use them/want them.
Common name: Fish (minnow)
Scientific name: Pimephales notatus
Ecological principles: Commensal and non domesticated because they are not usually pets or food. Other fish may be domesticated because they are used for food.
Common name: Crow
Scientific name: Corvus brachyrhynchos
Ecological principles: Non domesticated. Commensal. We do not usually have a crow for pets.
Common name: Water Spider
Scientific name: Argyroneta aquatica.
Ecological principles: Commensal and non domesticated because these are not used as pets.
Scientific name: Argyroneta aquatica.
Ecological principles: Commensal and non domesticated because these are not used as pets.
Common name: Skunk
Scientific name: mephitis mephitis
Ecological principles: Non domisticated, commesal. People usually do not own them as pets.
Scientific name: mephitis mephitis
Ecological principles: Non domisticated, commesal. People usually do not own them as pets.
Common name: facial bacteria
Scientific name: Hafnia
Ecological principles: non domesticated, we do not use them voluntarily or want them.
chapters 16, 17, 22-24 compendium reviews
Chapter 16
Human Life Cycle
*2 types of cell divisions
*Mitosis:
*Growth and repair of the tissues
*Meiosis:
*Gamete production
The Reproductive Systems
Male:
*Penis-organ of sexual intercourse
*Scrotum-contains the testes
*Spermatogenesis-occurs in the seminiferous tubules of the testes-produces sperm.
*Mature sperm are stored in the epididymides.
*Sperm pass from the vasa deferentia to the urethra.
*The seminal vesicles, prostate gland, and the bulbourethral glands add fluids to sperm.
*Sperm and secretions are called semen or seminal fluid.
*Orgasm in males results in ejaculation of semen from the penis.
Hormonal regulation in males
*Hormonal regulation, involving secretions from the hypothalamus, the anterior pituitary, and the testes, maintains a fairly constant level of testosterone.
*FSH from the anterior pituitary promotes spermatogenesis
*LH from the anterior pituitary promotes testosterone production by the interstitial cells
Female:
*Oogenesis occurring within the ovaries typically produces one mature follicle each month
*This follicle balloons out of the ovary and bursts, releasing an egg that enters an oviduct.
*The oviducts lead to the uterus, where implantation and development occur
*The female external genital area includes the vaginal opening, the clitoris, the labia minora, and the labia majora.
*The vagina is the organ of sexual intercourse and the birth canal in the female.
*Orgasm in females culminates in uterine and oviduct contrations
Female Hormone Levels
Ovarian Cycle: Nonpregnant
*The ovarian cycle is under the hormonal control of the hypothalamus and the anterior pituitary.
*During the cycle’s first half, FSH from the anterior pituitary causes maturation of a follicle that secretes estrogen and some progesterone.
*After ovulation and during the cycle’s second half, LH from the anterior pituitary converts the follicle into the corpus luteum.
*The corpus luteum secretes progesterone and some estrogen.
Uterine Cycle: Nonpregnant
*Estrogen and progesterone regulate the uterine cycle
*Estrogen causes the endometrium to rebuild
*Ovulation usually occurs day 14 of a 28 day cycle
*Progesterone produced by the corpus luteum causes the endometrium to thicken and become secretory.
*A low level of hormones causes the endometrium to break down as menstruation occurs.
Fertilization and pregnancy
*If fertilization takes place, the embryo implants itself in the thickened endometrium.
*The corpus luteum is maintained because of HCG production by the placenta, and therefore, progesterone production does not cease.
*Menstruation usually does not occur during pregnancy.
Control of Reproduction
*Numerous birth control methods and devices are available
*A few of these are birth control pills, diaphragm, and condom
*Effectiveness varies
*Assisted reproductive technologies help infertile couples have children
*Artificial insemination by a donor.
*In vitro fertilization
*Gamete intrafallopian transfer
*Intracytoplasmic sperm injection
Sexually Transmitted Diseases
*STDs are caused by viruses, bacteria, protists, fungi, and animals.
STDs caused by viruses
*AIDS is caused by HIV
*Genital warts are caused by the human papillomaviruses. These viruses cause warts or lesions on genitals and are associated with certain cancers.
*Genital herpes is caused by herpes simplex virus type 2. It causes blisters on genitals.
*Hepititis is caused by hepatitis viruses A, B, C, D, E, and G. A and E are usually acquired from contaminated water. B and C are from bloodborne transmission. B, D, and G are sexually transmitted.
STDs caused by bacteria
*Chlamydia is caused by Chlamydia trachomtis; PID can result.
*Gonorrhea is caused by Neisseria gonorrhoea; PID can result.
*Syphilis is caused by Treponema pallidum; It has three stages, with the third resulting in death.
Two other infections
*Bacterial vaginosis is caused by Gardnerella vaginalis.
*Trichomoniasis is an overgrowth of Candida albicans.
Chapter 17
Fertilization
*The acrosome of a sperm releases enzymes that digest a pathway for the sperm through the zona pellucida. The sperm nucleus enters the egg and fuses with the egg nucleus.
Pre-Embryonic and Embryonic Development
*Cleavage, growth, morphogenesis, and differentiation are the processes of development.
*The extraembryonic membranes (chorion, allantois, yolk sac, and amnion), function in internal development.
Fetal Development
*At the end of the embryonic period, all organ systems are established, and there is a mature and functioning placenta.
*The umbilical arteries and umbilical vein take blood to and from the placenta, where exchanges take place.
*Exchanges supply the fetus with oxygen and nutrients and rid the fetus of carbon dioxide and wastes.
*The venous duct joins the umbilical vein to the inferior vena cava.
*The oval duct and the arterial duct allow the blood to pass through the heart without going to the lungs.
*Fetal development extends from the third through the ninth months.
*During the third and fourth months, the skeleton is becoming ossified.
*The sex of the fetus becomes distinguishable. If an SRY gene is present, testes and male genitals develop. Otherwise, ovaries and female genitals develop.
*During the fifth through the ninth months, the fetus continues to grow and gain weight.
Pregnancy and Birth
*Major changes take place in the mother’s body during pregnancy
*Weight gain occurs as the uterus occupies most of the abdominal cavity.
*Many complains, such as constipation, heartburn, darkening of certain skin areas, and pregnancy induced diabetes, are due to the presence of placental hormones.
Birth
*A positive feedback mechanism that involves uterine contractions and oxytocin explains the onset and continuation of labor.
*During stage 1 of parturition (birth), the cervix dialates
*Stage 2-child is born
*Stage 3-afterbirth is expelled
Development After Birth
*Development after brith consists of infancy, childhood, adolescence, and adulthood
*Aging encompasses progressive changes from about age 20 on that contribute to an increased risk of infirmity, disease, and death.
Hypothesis of Aging
*May have a genetic basis
*May be due to changes that affect the whole body
*May be due to extrinsic factors
Effect of age on Body Systems
*Deterioration of organ systems can possibly be prevented or reduced in part by utilizing good health habits.
Chapter 22
Origin of Life
*Chemical evolution could have produced the protocell
*Using an outside energy source, small organic molecules were produced by reactions between early Earth’s atmospheric gases.
*Macromolecules evolved and interacted
*The RNA first hypothesis-only macromolecule RNA was needed for the first cells
*The protein first hypothesis-amino acids join to form polypeptides when exposed to dry heat
*The protocell, a heterotrophic fermenter, lived on preformed organic molecules in the ocean.
*The protocell eventually became a true cell once it had genes composed of DNA and could reproduce.
Biological Evolution
*Biological evolution explains both the unity and diversity of life
*Descent from a common ancestor explains the unity of living things
*Adaptation to different environments explains the great diversity of living things
*Fossil evidence supports evolution---the fossil record gives us the history of life in general and allows us to trace the descent of a particular group
*Darwin discovered much evidence for common descent
*Biogeographical evidence---the distribution of organisms on Earth is explainable by assuming that organisms evolved in one locale
*Anatomical evidence---the common anatomies and development of a group of organisms are explainable by descent from a common ancestor
*Biochemical evidence---all organisms have similar biochemical molecules
*Darwin development a mechanism for adaptation known as natural selection
*The result of natural selection is a population adapted to its local environment
Classification of Humans
*The classification of humans can be used to trace their ancestry
*Humans are primates
*A primate evolutionary tree shows that humans share a common ancestor with African apes
Evolution of Hominids
*The first hominid most likely lived about 6-7mya
*Certain features identify fossil hominids
*Ardipithecines were most likely hominids
Evolution of Australopithecines
*The evolutionary tree of hominids resembles a brush
*Australopithecines lived about 3mya
*They could walk, erect, but they had a small brain
*This testifies to a mosaic evolution for humans
Evolution of Humans
*Fossils are classified as Homo with regard to brain size (over 600cm^3), jaws and teeth, and evidence of tool use.
*H. habilis made and used tools
*H. erectus was the first Homo to have a brain size of more than 1000cm^3
*H. erectus migrated from Africa into Europe and Asia
*H. erectus used fire and may have been big-game hunters.
Evolution of Modern Humans
*Two hypotheses of modern human evolution are being tested
*The multiregional continuity hypothesis suggests that modern humans evolved separately in Europe, Africa, and Asia
*The out of Africa hypothesis says that H. sapiens evolved in Africa but then migrated to Asia and Europe
Neandertals and Cro-Magnons
*The Neandertals were already living in Europe and Asia before modern humans arrived
*They had a culture, but did not have the physical traits of modern humans
*Cro-Magnons are the oldest fossil to be designated H. sapiens. Their tools were sophisticated, and they had a culture.
Chapter 23
The Nature of Ecosystems
*Ecology is the study of the interactions of organisms with each other and wit the physical environment
*Organisms interact with the physical and chemical environment, and the result is an ecosystem
*Terrestrial ecosystems are forests (tropical rain forests, coniferous, temperate deciduous), grasslands (savanna and prairie), and deserts, which includes the tundra
*Aquatic ecosystems are either salt water or freshwater
Biotic Components of an Ecosystem
*In a community, each population has a habitat (residence) and a niche (role in the environment)
*Autotrophs produce organic nutrients for themselves and others from inorganic nutrients and outside energy sources
*Heterotrophs consume organic nutrients
*Consumers are herbivores, carnivores, and omnivores
*Decomposers feed on detritus, releasing inorganic substances back into the ecosystem
Energy Flow and Chemical Cycling
*Ecosystems are characterized by energy flow and chemical cycling
*Energy flows through the populations of an ecosystem
*Chemicals cycle within and among ecosystems
Energy Flow
*Various interconnecting paths of energy flow are called a food web
*A food web is a diagram showing how various organisms are connected by eating relationships
*Grazing food webs begin with vegetation eaten by a herbivore that becomes food for a carnivore
*Detrital food webs begin with detritus food for decomposers and for detritivores
*Members of detrital food webs can be eaten by aboveground carnivores, joining the two food webs
Trophic Levels
*A trophic level is all the organisms that feed at a particular link in a food chain
*Ecological pyramids illustrate that biomass and energy content decrease from one trophic level to the next because of energy loss.
Global Biogeochemical Cycles
*Chemicals circulate through ecosystems via biogeochemical cycles, pathways involving both biotic and geological components.
*can be gaseous or sedimentary
*have reservoirs that contain inorganic nutrients available to living things on a limited basis
*Exchange pools are sources of inorganic nutrients
*Nutrients cycle among the biotic communities of an ecosystem
The water cycle
*The reservoir of the water cycle is freshwater that evaporates from the ocean
*Water that falls on land enters the ground, surface waters, or aquifers, and evaporates again
*All water returns to the ocean
The carbon cycle
*The reservoirs of the carbon cycle are organic matter, limestone, and the ocean
*The exchange pool is the atmosphere
*Photosynthesis removes carbon dioxide from the atmosphere
*Respiration and combustion add carbon dioxide to the atmosphere
The nitrogen cycle
*The reservoir of the nitrogen cycle is the atmosphere
*Nitrogen gas must be converted to a form usable by plants
*Nitrogen-fixing bacteria convert nitrogen gas to ammonium
*Nitrifying bacteria convert ammonium to nitrate
*Denitrifying bacteria convert nitrate back to nitrogen gas
The phosphorus cycle
*The reservoir of the phosphorus cycle is ocean sediments
*Phosphate in ocean sediments become available through geological upheaval, which exposes sedimentary rocks to weathering
*Weathering slowly makes phosphate available to the biotic community
*Phosphate is a limited nutrient in ecosystems
Chapter 24
Human Population Growth
*Populations have a biotic potential for increase in size
*Biotic potential is normally held in check by environmental resistance
*Population size usually levels off at carrying capacity
The MCDs vs the LDCs
*The MCDs have a .1% growth rate since 1950
*The LDC Growth rate is presently at 1.6% after peaking at 2.5% in the 1960s
*Age structural diagrams can be used to predict population growth
*MCDs are approaching a stable population size
*LDC populations will continue to increase in their size
Human Use of Resources and Pollution
*Five resources are maximally used by humans
*They are either renewable or nonrenewable
*Nonrenewable resources are not replenished and are limited in quantity
*Renewable resources are replenished but still are limited in quantity
Land
*Human activities, such as habitation, farming, and mining, contribute to erosion, pollution, desertification, deforestation, and loss of biodiversity
Water
*Industry and agriculture use most of the freshwater supply. Water supplies are increased by damming river and drawing from aquifers.
Food
*Food comes from growing crops, raising animals, and fishing
*Modern farming methods increase the food supply but some methods harm the land, pollute the water, and consume excessive fossil fuels
*Genetically engineered plants increase the food supply and reduce the need for chemicals
*Raising livestock contributes to water pollution and uses fossil fuel energy
*The increased number and high efficiency of fishing boats have caused the world fish catch to decline
Energy
*Fossil fuels are nonrenewable sources.
*Greenhouse gases include CO2 and other gases. Greenhouse gases cause global warming because solar radiation can pass through, but infrared heat cannot escape back into space
*Renewable resources include hydropower, geothermal, wind, and solar powers
Minerals
*Minerals are nonrenewable resources that can be mined
*Include sand, gravel, phosphate, and metals
*Mining causes destruction of the land by erosion, loss of vegetation, and toxic runoff into bodies of water.
*Hazardous wastes are discarded on land and water in the billions
*Heavy metals
*Synthetic organic chemicals include chlorofluorocarbons, which are involved in the production of plastics, pesticides, herbicides, and other products
*Ozone shield destruction is associated with CFCs
*Other synthetic organic chemicals enter the aquatic food chain, where the toxins become more concentrated
Biodiversity
*variety of life on Earth
*five major causes of biodiversity loss and extinction
*Habitat loss
*Introduction of alien species
*pollution
*Overexploitation of plants and animals
*disease
Direct Value of Biodiversity
*medicinal value
*agricultural value
*consumptive use values
Indirect Value of Biodiversity
*contributes to waste disposal
*freshwater provision through the water biogeochemical cycle
*prevention of soil erosion, which occurs naturally in intact ecosystems
*function of biogeochemical cycles
*climate regulation
*ecotourism
Working Toward a Sustainable Society
*A sustainable society would use only renewable energy resources
Human Life Cycle
*2 types of cell divisions
*Mitosis:
*Growth and repair of the tissues
*Meiosis:
*Gamete production
The Reproductive Systems
Male:
*Penis-organ of sexual intercourse
*Scrotum-contains the testes
*Spermatogenesis-occurs in the seminiferous tubules of the testes-produces sperm.
*Mature sperm are stored in the epididymides.
*Sperm pass from the vasa deferentia to the urethra.
*The seminal vesicles, prostate gland, and the bulbourethral glands add fluids to sperm.
*Sperm and secretions are called semen or seminal fluid.
*Orgasm in males results in ejaculation of semen from the penis.
Hormonal regulation in males
*Hormonal regulation, involving secretions from the hypothalamus, the anterior pituitary, and the testes, maintains a fairly constant level of testosterone.
*FSH from the anterior pituitary promotes spermatogenesis
*LH from the anterior pituitary promotes testosterone production by the interstitial cells
Female:
*Oogenesis occurring within the ovaries typically produces one mature follicle each month
*This follicle balloons out of the ovary and bursts, releasing an egg that enters an oviduct.
*The oviducts lead to the uterus, where implantation and development occur
*The female external genital area includes the vaginal opening, the clitoris, the labia minora, and the labia majora.
*The vagina is the organ of sexual intercourse and the birth canal in the female.
*Orgasm in females culminates in uterine and oviduct contrations
Female Hormone Levels
Ovarian Cycle: Nonpregnant
*The ovarian cycle is under the hormonal control of the hypothalamus and the anterior pituitary.
*During the cycle’s first half, FSH from the anterior pituitary causes maturation of a follicle that secretes estrogen and some progesterone.
*After ovulation and during the cycle’s second half, LH from the anterior pituitary converts the follicle into the corpus luteum.
*The corpus luteum secretes progesterone and some estrogen.
Uterine Cycle: Nonpregnant
*Estrogen and progesterone regulate the uterine cycle
*Estrogen causes the endometrium to rebuild
*Ovulation usually occurs day 14 of a 28 day cycle
*Progesterone produced by the corpus luteum causes the endometrium to thicken and become secretory.
*A low level of hormones causes the endometrium to break down as menstruation occurs.
Fertilization and pregnancy
*If fertilization takes place, the embryo implants itself in the thickened endometrium.
*The corpus luteum is maintained because of HCG production by the placenta, and therefore, progesterone production does not cease.
*Menstruation usually does not occur during pregnancy.
Control of Reproduction
*Numerous birth control methods and devices are available
*A few of these are birth control pills, diaphragm, and condom
*Effectiveness varies
*Assisted reproductive technologies help infertile couples have children
*Artificial insemination by a donor.
*In vitro fertilization
*Gamete intrafallopian transfer
*Intracytoplasmic sperm injection
Sexually Transmitted Diseases
*STDs are caused by viruses, bacteria, protists, fungi, and animals.
STDs caused by viruses
*AIDS is caused by HIV
*Genital warts are caused by the human papillomaviruses. These viruses cause warts or lesions on genitals and are associated with certain cancers.
*Genital herpes is caused by herpes simplex virus type 2. It causes blisters on genitals.
*Hepititis is caused by hepatitis viruses A, B, C, D, E, and G. A and E are usually acquired from contaminated water. B and C are from bloodborne transmission. B, D, and G are sexually transmitted.
STDs caused by bacteria
*Chlamydia is caused by Chlamydia trachomtis; PID can result.
*Gonorrhea is caused by Neisseria gonorrhoea; PID can result.
*Syphilis is caused by Treponema pallidum; It has three stages, with the third resulting in death.
Two other infections
*Bacterial vaginosis is caused by Gardnerella vaginalis.
*Trichomoniasis is an overgrowth of Candida albicans.
Chapter 17
Fertilization
*The acrosome of a sperm releases enzymes that digest a pathway for the sperm through the zona pellucida. The sperm nucleus enters the egg and fuses with the egg nucleus.
Pre-Embryonic and Embryonic Development
*Cleavage, growth, morphogenesis, and differentiation are the processes of development.
*The extraembryonic membranes (chorion, allantois, yolk sac, and amnion), function in internal development.
Fetal Development
*At the end of the embryonic period, all organ systems are established, and there is a mature and functioning placenta.
*The umbilical arteries and umbilical vein take blood to and from the placenta, where exchanges take place.
*Exchanges supply the fetus with oxygen and nutrients and rid the fetus of carbon dioxide and wastes.
*The venous duct joins the umbilical vein to the inferior vena cava.
*The oval duct and the arterial duct allow the blood to pass through the heart without going to the lungs.
*Fetal development extends from the third through the ninth months.
*During the third and fourth months, the skeleton is becoming ossified.
*The sex of the fetus becomes distinguishable. If an SRY gene is present, testes and male genitals develop. Otherwise, ovaries and female genitals develop.
*During the fifth through the ninth months, the fetus continues to grow and gain weight.
Pregnancy and Birth
*Major changes take place in the mother’s body during pregnancy
*Weight gain occurs as the uterus occupies most of the abdominal cavity.
*Many complains, such as constipation, heartburn, darkening of certain skin areas, and pregnancy induced diabetes, are due to the presence of placental hormones.
Birth
*A positive feedback mechanism that involves uterine contractions and oxytocin explains the onset and continuation of labor.
*During stage 1 of parturition (birth), the cervix dialates
*Stage 2-child is born
*Stage 3-afterbirth is expelled
Development After Birth
*Development after brith consists of infancy, childhood, adolescence, and adulthood
*Aging encompasses progressive changes from about age 20 on that contribute to an increased risk of infirmity, disease, and death.
Hypothesis of Aging
*May have a genetic basis
*May be due to changes that affect the whole body
*May be due to extrinsic factors
Effect of age on Body Systems
*Deterioration of organ systems can possibly be prevented or reduced in part by utilizing good health habits.
Chapter 22
Origin of Life
*Chemical evolution could have produced the protocell
*Using an outside energy source, small organic molecules were produced by reactions between early Earth’s atmospheric gases.
*Macromolecules evolved and interacted
*The RNA first hypothesis-only macromolecule RNA was needed for the first cells
*The protein first hypothesis-amino acids join to form polypeptides when exposed to dry heat
*The protocell, a heterotrophic fermenter, lived on preformed organic molecules in the ocean.
*The protocell eventually became a true cell once it had genes composed of DNA and could reproduce.
Biological Evolution
*Biological evolution explains both the unity and diversity of life
*Descent from a common ancestor explains the unity of living things
*Adaptation to different environments explains the great diversity of living things
*Fossil evidence supports evolution---the fossil record gives us the history of life in general and allows us to trace the descent of a particular group
*Darwin discovered much evidence for common descent
*Biogeographical evidence---the distribution of organisms on Earth is explainable by assuming that organisms evolved in one locale
*Anatomical evidence---the common anatomies and development of a group of organisms are explainable by descent from a common ancestor
*Biochemical evidence---all organisms have similar biochemical molecules
*Darwin development a mechanism for adaptation known as natural selection
*The result of natural selection is a population adapted to its local environment
Classification of Humans
*The classification of humans can be used to trace their ancestry
*Humans are primates
*A primate evolutionary tree shows that humans share a common ancestor with African apes
Evolution of Hominids
*The first hominid most likely lived about 6-7mya
*Certain features identify fossil hominids
*Ardipithecines were most likely hominids
Evolution of Australopithecines
*The evolutionary tree of hominids resembles a brush
*Australopithecines lived about 3mya
*They could walk, erect, but they had a small brain
*This testifies to a mosaic evolution for humans
Evolution of Humans
*Fossils are classified as Homo with regard to brain size (over 600cm^3), jaws and teeth, and evidence of tool use.
*H. habilis made and used tools
*H. erectus was the first Homo to have a brain size of more than 1000cm^3
*H. erectus migrated from Africa into Europe and Asia
*H. erectus used fire and may have been big-game hunters.
Evolution of Modern Humans
*Two hypotheses of modern human evolution are being tested
*The multiregional continuity hypothesis suggests that modern humans evolved separately in Europe, Africa, and Asia
*The out of Africa hypothesis says that H. sapiens evolved in Africa but then migrated to Asia and Europe
Neandertals and Cro-Magnons
*The Neandertals were already living in Europe and Asia before modern humans arrived
*They had a culture, but did not have the physical traits of modern humans
*Cro-Magnons are the oldest fossil to be designated H. sapiens. Their tools were sophisticated, and they had a culture.
Chapter 23
The Nature of Ecosystems
*Ecology is the study of the interactions of organisms with each other and wit the physical environment
*Organisms interact with the physical and chemical environment, and the result is an ecosystem
*Terrestrial ecosystems are forests (tropical rain forests, coniferous, temperate deciduous), grasslands (savanna and prairie), and deserts, which includes the tundra
*Aquatic ecosystems are either salt water or freshwater
Biotic Components of an Ecosystem
*In a community, each population has a habitat (residence) and a niche (role in the environment)
*Autotrophs produce organic nutrients for themselves and others from inorganic nutrients and outside energy sources
*Heterotrophs consume organic nutrients
*Consumers are herbivores, carnivores, and omnivores
*Decomposers feed on detritus, releasing inorganic substances back into the ecosystem
Energy Flow and Chemical Cycling
*Ecosystems are characterized by energy flow and chemical cycling
*Energy flows through the populations of an ecosystem
*Chemicals cycle within and among ecosystems
Energy Flow
*Various interconnecting paths of energy flow are called a food web
*A food web is a diagram showing how various organisms are connected by eating relationships
*Grazing food webs begin with vegetation eaten by a herbivore that becomes food for a carnivore
*Detrital food webs begin with detritus food for decomposers and for detritivores
*Members of detrital food webs can be eaten by aboveground carnivores, joining the two food webs
Trophic Levels
*A trophic level is all the organisms that feed at a particular link in a food chain
*Ecological pyramids illustrate that biomass and energy content decrease from one trophic level to the next because of energy loss.
Global Biogeochemical Cycles
*Chemicals circulate through ecosystems via biogeochemical cycles, pathways involving both biotic and geological components.
*can be gaseous or sedimentary
*have reservoirs that contain inorganic nutrients available to living things on a limited basis
*Exchange pools are sources of inorganic nutrients
*Nutrients cycle among the biotic communities of an ecosystem
The water cycle
*The reservoir of the water cycle is freshwater that evaporates from the ocean
*Water that falls on land enters the ground, surface waters, or aquifers, and evaporates again
*All water returns to the ocean
The carbon cycle
*The reservoirs of the carbon cycle are organic matter, limestone, and the ocean
*The exchange pool is the atmosphere
*Photosynthesis removes carbon dioxide from the atmosphere
*Respiration and combustion add carbon dioxide to the atmosphere
The nitrogen cycle
*The reservoir of the nitrogen cycle is the atmosphere
*Nitrogen gas must be converted to a form usable by plants
*Nitrogen-fixing bacteria convert nitrogen gas to ammonium
*Nitrifying bacteria convert ammonium to nitrate
*Denitrifying bacteria convert nitrate back to nitrogen gas
The phosphorus cycle
*The reservoir of the phosphorus cycle is ocean sediments
*Phosphate in ocean sediments become available through geological upheaval, which exposes sedimentary rocks to weathering
*Weathering slowly makes phosphate available to the biotic community
*Phosphate is a limited nutrient in ecosystems
Chapter 24
Human Population Growth
*Populations have a biotic potential for increase in size
*Biotic potential is normally held in check by environmental resistance
*Population size usually levels off at carrying capacity
The MCDs vs the LDCs
*The MCDs have a .1% growth rate since 1950
*The LDC Growth rate is presently at 1.6% after peaking at 2.5% in the 1960s
*Age structural diagrams can be used to predict population growth
*MCDs are approaching a stable population size
*LDC populations will continue to increase in their size
Human Use of Resources and Pollution
*Five resources are maximally used by humans
*They are either renewable or nonrenewable
*Nonrenewable resources are not replenished and are limited in quantity
*Renewable resources are replenished but still are limited in quantity
Land
*Human activities, such as habitation, farming, and mining, contribute to erosion, pollution, desertification, deforestation, and loss of biodiversity
Water
*Industry and agriculture use most of the freshwater supply. Water supplies are increased by damming river and drawing from aquifers.
Food
*Food comes from growing crops, raising animals, and fishing
*Modern farming methods increase the food supply but some methods harm the land, pollute the water, and consume excessive fossil fuels
*Genetically engineered plants increase the food supply and reduce the need for chemicals
*Raising livestock contributes to water pollution and uses fossil fuel energy
*The increased number and high efficiency of fishing boats have caused the world fish catch to decline
Energy
*Fossil fuels are nonrenewable sources.
*Greenhouse gases include CO2 and other gases. Greenhouse gases cause global warming because solar radiation can pass through, but infrared heat cannot escape back into space
*Renewable resources include hydropower, geothermal, wind, and solar powers
Minerals
*Minerals are nonrenewable resources that can be mined
*Include sand, gravel, phosphate, and metals
*Mining causes destruction of the land by erosion, loss of vegetation, and toxic runoff into bodies of water.
*Hazardous wastes are discarded on land and water in the billions
*Heavy metals
*Synthetic organic chemicals include chlorofluorocarbons, which are involved in the production of plastics, pesticides, herbicides, and other products
*Ozone shield destruction is associated with CFCs
*Other synthetic organic chemicals enter the aquatic food chain, where the toxins become more concentrated
Biodiversity
*variety of life on Earth
*five major causes of biodiversity loss and extinction
*Habitat loss
*Introduction of alien species
*pollution
*Overexploitation of plants and animals
*disease
Direct Value of Biodiversity
*medicinal value
*agricultural value
*consumptive use values
Indirect Value of Biodiversity
*contributes to waste disposal
*freshwater provision through the water biogeochemical cycle
*prevention of soil erosion, which occurs naturally in intact ecosystems
*function of biogeochemical cycles
*climate regulation
*ecotourism
Working Toward a Sustainable Society
*A sustainable society would use only renewable energy resources
Sunday, May 11, 2008
no worries
everything will be posted tomorrow when i get off of work!! I really enjoyed these chapters!
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