L 4.5.2 Test (CST): Ecology Question 14 of 25
Which phrase describes a keystone species?
A. The species that uses the most resources in an area
B. A species that preys on all the other species in a community
C. The first species to colonize an area
O O
D. A species that is crucial to the health of a commun
SUBMIT

The answer would be c, white eyes are homozygous recessive. in the early 1900s, morgan conducted several experiments with vinegar  flies (drosophila). one  sample revealed an anomaly: a  white-eyed, single male fly. he attempted to breed this fly with the typical red-eyed females. the offspring were all red-eyed. using flies from this new generation (brother-sister pairs)  produced some red-eyed and a few white-eyed flies. the white-eyed were all male. in later experiments, he was able to produce white-eyed females. this proved that white eyes are not lethal to either sex (ruling out a and b). since the percentage of white eyes to red eyes is so low, white eyes are not a dominant trait. it would be a recessive trait.