In Drosophila melanogaster, ebony body color is determined by the e allele. The e+ allele produces the wild-type honey-colored body. In heterozygotes, the body is honey-colored except for a dark marking called the trident seen on the thorax. The e+ allele is thus considered to be incompletely dominant to the e allele. a. When female e+ e+ flies are crossed to male e+ e flies, what is the probability that progeny will have the trident marking? Animals with the marking mate among themselves. Of 100 progeny, how many would be expected to have a trident, how many would have ebony bodies, and how many would have honey-colored bodies?

Write the cross using correct symbols. What kind of cross is this called?

The presence of horns on satyrs is produced by a sex-influenced autosomal gene that is dominant in males and recessive in females. A horned female is crossed with a hornless male. The F1 are then intercrossed to produce the F2. What proportion of the F2 generation will be horned? O % of the males and none of the females O % of males and % of females O All of the males and none of the females O % of the males and % of females O ½ of the males and none of the females

In fruit flies, red eyes (E) are dominant to white eyes (e). Cross two heterzygotes.  a. What are the possible genotypes for red eyes ? b. What are the possible genotype(s) for white eyes ?

The data set attached summarizes F2 numbers from an F1 cross arising from two, true-breeding Drosophila strains (P generation), which differ with respect to two mutant traits. Here are the hypothesis: Leg length - The wild-type and mutant alleles for leg length are incomplete dominant relative to each other. Justification: The data set includes three phenotypic categories for leg length: wild type (long leg), medium leg, and truncated wings. The presence of three distinct phenotypes suggests an incomplete dominance pattern, where the heterozygous individuals exhibit an intermediate leg length phenotype (medium leg). The absence of purebred short-legged individuals supports the idea that the long leg allele is dominant over the short leg allele. This shows that mode of inheritance is incomplete dominance of the alleles relative to each other. Since the data does not mention any specific differences between males and females, we can assume that the mode of inheritance for the trait is…

In garden pea, resistance to a certain disease is controlled by a single locus with dominance forresistance (R) and recessive susceptible (r). Another locus governs seed color with yellow being dominant (Y)to green (y). A pea plant which is heterozygous for both gene pairs is crossed with a susceptible and green-seeded plant. The following data was observed in the progeny. Phenotype                                NumberResistant yellow                           43Susceptible green                         49Resistant green                             16Susceptible yellow                         12Total                                               120 a. What is the calculated chi-square value based on an independent assortment assumption? Compute forthe df and write the conclusion. (NOTE: The cross will not yield a 9:3:3:1 ratio since not both of theparental genotypes are heterozygous for the 2 pairs of alleles. Thus, perform the cross first, show theparental genotypes, the gamete…