A tall pea plant results from a dominant tall allele. A short phenotype requires that an individual has two recessive alleles. A short pea plant (pp) is crossed with a tall pea plant (Pp).

Question

What is the frequency of short offspring (pp) from this crossing?

(1 point)
Responses

0.75
0.75

0.5
0.5

0.25
0.25

1.0

Answer 1

To determine the frequency of short offspring (pp) from crossing a short pea plant (pp) with a tall pea plant (Pp), we can set up a Punnett square.

The genotypes involved are:

• Short pea plant: pp
• Tall pea plant: Pp

When we cross these:

• The tall plant (Pp) can contribute either a dominant allele (P) or a recessive allele (p).
• The short plant (pp) can only contribute a recessive allele (p).

The possible combinations from this cross are:

• If the tall plant contributes P, the offspring will be Pp (tall).
• If the tall plant contributes p, the offspring will be pp (short).

So the potential offspring genotypes are:

• 50% Pp (tall)
• 50% pp (short)

Thus, the frequency of short offspring (pp) from this cross is 0.5 (or 50%).

The correct answer is 0.5.