Their Dna To A Certain Population example essay topic

Bill Law Intro. To Anthropology Prof. Salazar 4 February 2003 A Theory Evolves 1. Darwin was unable to explain the manner in which life, specifically the genetic makeup of a life form could change to allow natural selection to occur. The modern synthesis of genetics and the new evolutionary theory filled in the gap by explaining the occurrences of mutation and other sources of variation in a population through a genetic change in the populations DNA, whereby the population slowly changes until the environment becomes unstable for one of the populations and natural selection eliminates it.

2. The first line of evidence that confirms Darwin's theories is that Through testing, scientists have been able to confirm that certain butterflies produce offspring more successfully at higher temperatures than others. This confirms Darwin's idea of species changing to better suit the environment in which they inhabit. The second line of evidence shows that Darwin was also correct in his hypothesis that this process of change in a specie's DNA could change suddenly and spawn a whole new creature. This is characteristic with species like earthworms and arthropods. 3.

Darwin's understanding of evolution is limited when the relationship between the climate and the species in that environment. This is confirmed by the fossil evidence, or lack there of, in the world. The planet has faced many harsh climate and environment changes that have rapidly killed off many species for which there is no evidence of their existence. This explains why there may seem to be a significant change in a species without the long process of mutation and it could explain why species do not appear to have ancestors that are more similar to themselves... 4. This evo-dev o concept may help explain the evolution of species from millions of years ago.

It may help reveal hoe creatures changed into a new creature with different characteristics such as the many-legged arthropod changing into six-legged insects. 5. Home otic genes act as the master switches for characteristics such as physical features or other produced tissues. 6. The text demonstrates that a few mutations in the Hox gene can turn a many-legged arthropod into six-legged insects.

7. According to the text, evolution works with whatever it has. It adapts and modifies current DNA into a variation of genetic makeup until a successful trait is found. 8.

Knoll says that the day after the meteorite hit the earth, the environment began to heal itself, whereas this form of extinction will only continue as long as human evolution continues. 9. Evolution should remain in schools because it is the key to understanding life and curing diseases like HIV. BY understanding the complex nature of evolution, a cure may be found for many diseases. Curse and Blessing of the Ghetto 1. Infants with Tay-Sachs disease inherit it from their parents.

First, the infant seems normal until a few months passes, then, an unusual reaction to sounds will be expressed by the child. Then, the child will lose control of its motor functions in its head and it will progress to drooling, convulsions, and sporadic bursts of laughter. Next, the infant's head will grow large and blindness sets in. Finally, the child will be reduced to a vegetative state where its skin will turn into a yellowish color and its hands will swell.

Death will usually occur around this stage. 2.1 in every 400,000 people. 1 in every 3,600 people. 3. A characteristic in the population causes this disease to be carried recessively and every infant contracting the disease will have inherited it recessively from their parents.

4. The disease is a homozygote. 5. The first explanation is that new copies of the gene are replacing the existing genes with the disease by mutation. The second explanation is that the population might have inherited the disease from another population that had the gene in a high frequency. The third explanation is a combination of the founder effect and genetic drift which resulted in a population with a higher frequency of this disease.

6. The population for genetic drift and the founder effect have to be very small, however these populations are rather large. Also, the communities were very widespread which would make drift very unlikely. 7. The number of grandparents who died of TB was about 20%. Tay-Sachs may protect against TB.

8. Jewish cultures have been forced to live in towns for thousands of years, confining themselves abd their DNA to a certain population. They were forced to live in crowded ghettos in unsanitary conditions which led to a TB resistance. 9.

Some questions that still need to be answered are whether or not the biochemical mechanisms by which fat accumulation can be used for resisting TB or why there is a low frequency of TB deaths in the grandparents. The Saltshaker's Curse 1. American Blacks have higher blood pressure. They have a higher risk of developing hypertension, heart disease, kidney failure, and are less likely to die from a stroke that Japanese Americans. 2. Three environmental factors are obesity, high consumption of salt or alcohol, and low calcium consumption.

3. It is possible that salt intake triggers thirst which increases blood volume, however, there are many causes of high blood pressure. 4. Blacks and whites do not differ much on their salt consumption but blacks have more stress and less access to medical care. Blacks retain salt longer than whites, and they have a greater risk of high blood pressure on a high salt diet.

5. American blacks have more access to salt, which the text points out is on every table, and they may not have adjusted to such a high salt diet. In West Africa, salt is scarce and is not consumed as much. Black, White, Other 1.

Biological race is the race inherited through genetics by a person's parents. Social race is the manner in which people act within a certain race, but, a person does not have to be a member of that biological race to act like it. 2. Symbolic and abstract differences mark members from nonmembers. They serve to distinguish people who are not distinguished in nature, as the text says. 3.

Genocidal violence is based on different skin color or physical features, but also more on cultural features of a population as well 4. "The anatomical features that distinguish people are distributed along geographical gradients, as are nearly all the genetically determined variants detectable in the human gene pool (Marks 47).".