Which of the following is not a form of natural pollution?
a. volcanic ash
c. forest fires
b. oil spills
d. all are forms of natural pollution

Amoeba sisters video recap pedigrees

Freckles are a dominant trait in humans. both of the girls have the genotype ff for freckles. if either one marries a man with no freckles, what are the chances that their children will have freckles?

How does the nervous system affect the excretory system?