Question

Two pea plants with yellow peas are crossed. Most of their offspring have yellow peas, but about 25 percent of the offspring have green peas. For pea color, yellow is the dominant trait and green is the recessive trait. What does this tell you about the two parent plants?

A. The parent plants have only dominant alleles for pea color.
B. The parent plants are heterozygous for pea color.
C. Pea color follows an incomplete dominance pattern of inheritance.
D. The parent plants are homozygous for pea color.

Answer 1

B. The parent plants are heterozygous for pea color.

Step-by-step explanation:

Answer 2

B. The parent plants are heterozygous for pea color.

Step-by-step explanation:

If both the parent plants had only dominant alleles for pea color as described in A, all of their offspring would be yellow (dominant). We know that pea color does not follow an incomplete dominance pattern because the question states that yellow is dominant and green is recessive; there is no intermediate mixture of these colors as a trait. If the parents were both homozygous, then their offspring would either be all yellow or all green. If we do a punnett square with 2 heterozygous parents, we will see that one out of 4 (25%) offspring will indeed be green.