In fruit flies, the allele (n) for a black body is recessive to the allele (N) for grey body. What would the next generation look like with two heterozygous parents.

There are certain words that need to be defined before answering the question, just to make sure that it is fully understood.Allele = a different form of a gene Heterozygous = in each fruit fly, there are two copies of each gene. A heterozygous fruit fly has one of each allele as a copy.This means that is you look at the genotype of each parent, it would be "Nn". We now need to work out what the possible genotypes of each offspring could be. For this we use a Punnet Square.Using a Punnet Square we can see that there are 4 possible genotypes: NN, Nn, Nn or nn.These genotypes are what the genetic code says, but we can oly see this from the phenotype which is the "characteristic expressed by a specific gene".In this case:a) NN would be the genotype and "grey" the phenotype.b) Nn would be the genotype and "grey" the phenotype as the N is dominant over the n.c) nn would be the genotype and "black" the phenotype as there in no N so the recessive n can be expressed.Looking at the Punnet Square, we can see that 3/4 contain N so would be grey and 1/4 doesn't so would be black.This means that the offspring would have a 75% chance of being grey and 25% chance of being black.