Question

in pea plants, tallness (t) is dominant to shortness (t). what are the predicted percentages of the genotypes of the offspring if a homozygous short plant is crossed with a heterozygous tall plant?
25 percent tt, 75 percent tt
25 percent tall, 75 percent short
50 percent tt, 50 percent tt
50 percent tall, 50 percent short

Explanation:

Step1: Determine the genotypes of the parents

A homozygous short plant has the genotype \( tt \). A heterozygous tall plant has the genotype \( Tt \).

Step2: Set up the Punnett square

The possible gametes from the \( tt \) parent are all \( t \). The possible gametes from the \( Tt \) parent are \( T \) and \( t \).

	\( T \)	\( t \)
\( t \)	\( Tt \)	\( tt \)

Step3: Analyze the genotypes of the offspring

From the Punnett square, there are 2 \( Tt \) and 2 \( tt \) genotypes out of 4 total. So the proportion of \( Tt \) is \( \frac{2}{4}=50\% \) and the proportion of \( tt \) is \( \frac{2}{4}=50\% \)

Answer:

50 percent \( Tt \), 50 percent \( tt \) (the third option)