There are both stimulatory and inhibitory proteins that help to regulate the cell cycle. Name one stimulatory protein and one inhibitory protein. At what point in the cell cycle are these proteins active and what are their effects on the cell cycle and the fate of the cell? Im pretty sure that the stimulatory protein is cycline-dependent kinases, and the inhibitory protein is retinoblastoma proteins, but I don't know what point in the cell cycle these proteins are active and what are their effects on the cell cyle and the fate of the cell.

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.