A tall pea plant results from a dominant tall allele while the short phenotype results from two recessive alleles. What is the frequency of short offspring (pp) when a tall pea plant with one tall allele (Pp) is cross-pollinated with a short pea plant (pp)?(1 point)

Question

Responses

0.25
0.25

0.5
0.5

1.0
1.0

0.75

Answer 1

To determine the frequency of short offspring (pp) from the cross of a tall pea plant with a genotype of Pp (heterozygous) and a short pea plant with a genotype of pp (homozygous recessive), we can set up a Punnett square.

The parental genotypes are:

• Pp (tall)
• pp (short)

The possible gametes from each parent are:

• Pp can produce P and p gametes.
• pp can only produce p gametes.

Now we can set up the Punnett square:

         P        p
      ----------------
   p |   Pp      pp
   p |   Pp      pp

From the Punnett square:

• The possible offspring genotypes are:
  • 2 Pp (tall)
  • 2 pp (short)

So, the frequency of short offspring (pp) is:

• 2 short (pp) out of 4 total offspring, which simplifies to 2/4 = 0.5.

Thus, the frequency of short offspring (pp) is 0.5.