Natural Selection is sometimes described as "survival of the fittest" which best measures an organisms fitness

a) how many fertile offspring it produces
b) its mutation rate
c) how strong it is when pitted againts other species
d) its ability to withstand environmental extremes
e) how much food it is able to make or maintain

Mutations are rarely the cause of evolution in populations of plants and animals because

a) they are often harmful and do not get passed on
b) they do not directly produce most of the genetic variation present in a diploid population
c) they occur very rarely
d) they are only passed on when they occur in cells that lead to gametes
e) all of the above

In an area of erratic rainfall , a biologist found that grass plants with alleles for curled leaves reproduced better in dry years , and plants with alleles for flat leaves reproduced better in wet years. This situation would tend to:

a) cause genetic drift in the grass population
b) preserve genetic variation on the grass population
c) lead to stabilizing selection in the grass population
d) lead to uniformity in the grass population
e) cause gene flow in the grass population

Which of the following pairs of structures is least likely to represent homology

a) the hemoglobin of a human and that of a baboon
b) the mitochondria of a plant and that of an animal
c) the wings of a bird and those of an insect
d) the tail of a cat and that of an alligator.
e) the foreleg of a pig and the flipper of a whale