The representation of the genotype of F1 generation is as follows:
Heterozygous red eye: Rr
The red eye is the phenotype and Rr is the genotype of F1 parental generation.
In F2 generation, the number of offspring that will have red eyes can be predicted by punnet squares represented in the image.
Offspring that are homozygous recessive (rr): 1 out of 4 or 1/4= 25%
Offspring that are heterozygous or homozygous dominant for red eyes (Rr and RR): 3 out of 4 or 3/4= 75%
Therefore, the probability that the F2 generation will have red eye is 3/4 or 75%
