If 2 spot (S) is dominant to 4 spot (s), give the genotypes for the parents in the following crosses (a) 2 spot 2 spot yields 2 spot and 4 spot
(b) 2 spot x 4 spot yields only 2 spot
(c) 2 spot x 4 spot yields 2 spot and 4 spot
(d) 2 spot x 2 spot yields only 2 spot
(e) 4 spot x 4 spot yields only 4 spot

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. 

Of the cold they can survive in the cold

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what are the options