Question

Scientists compare two different plant species. In species A, the leaf color is controlled by two alleles. In species B, leaf color is controlled by three alleles. How will these two plants be different?

A. Species B will have fewer genotypes.
B. Species B will have fewer phenotypes.
C. Species A will have more genotypes.
D. Species A will have fewer phenotypes.

Answer 1

The answer is D. Species A will have fewer phenotypes.
Alleles are alternative forms of a gene. In species A, the leaf color is controlled by two alleles, for example, P and Q. They will have three possible genotypes - PP, PQ, and QQ. Three different genotypes give maximum three phenotypes.In species B, leaf color is controlled by three alleles, for example, L, M, and N. They will have six different genotypes - LL, LM, LN, MM, MN, and NN. Six different genotypes give maximum 6 phenotypes.