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

The homozygous short plant has genotype \(tt\) (since shortness is recessive). The heterozygous tall plant has genotype \(Tt\) (tallness is dominant, and heterozygous means one dominant and one recessive allele).

Step2: Set up the Punnett square

The gametes of the \(tt\) plant are all \(t\). The gametes of the \(Tt\) plant are \(T\) and \(t\).

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

Step3: Analyze the genotypes of the offspring

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

Answer:

C. 50 percent \(Tt\), 50 percent \(tt\)