Describe an environmental factor that could
influence natural selection and decrease genetic
diversity. pick a specific example to illustrate your
point

A lot of toxins in a coral reef could influence natural selection so it would become like survival of the fittest. Then the fish would develop certain traits to better protect themselves (less prey means predators would takes bigger measures to get food). This would also cause a decrease genetic variation because there wouldn't be as much fish left. Since the coral reef went from unique to dull from toxins.

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."

1. b.

2. d.

3. a.

5. d.

6. c.

these are the only ones that i know, i hope this , and good luck.