You are given a monohybrid cross between a wild type fruit fly and a mutant fly called "apterous" (ap) which lacks wings. If both flies are homozygous, how would you denote the cross described

APAP  x  apap

Explanation:

Let us assume that the allele for wing is represented by ap.

The wild type is the strain that is common in natural condition, that is, winged condition. Hence, since both flies are homozygous, the mutant genotype is depicted as apap, while the wild type's genotype will be denoted as APAP.

The cross will be denoted as: APAP  x  apap

The offspring will be: APap, APap, APap and APap