In pea plants, tall plants (T) are dominant over short plants (t). If a heterozygous tall pea plant is crossed with a homozygous recessive short pea plant, what percentage of the offspring is expected to be tall.

Question

(HINT: use a Punnett square to help you with this question)

(1 point)
Responses

0%
0%

50%
50%

25%
25%

75%

Answer 1

To determine the expected percentage of tall offspring when crossing a heterozygous tall pea plant (Tt) with a homozygous recessive short pea plant (tt), we can set up a Punnett square.

• Parent 1 (heterozygous tall): Tt
• Parent 2 (homozygous recessive short): tt

The Punnett square will look like this:

        T      t
      __________
   t |   Tt   |   tt   |
      |_________|
   t |   Tt   |   tt   |
      |_________|

From the Punnett square, we can see the possible genotypes of the offspring:

• Tt (tall) - 2 squares
• tt (short) - 2 squares

This means that out of 4 possible combinations:

• 2 are tall (Tt)
• 2 are short (tt)

To find the percentage of tall offspring, we calculate:

\[ \frac{\text{Number of tall offspring}}{\text{Total offspring}} \times 100 = \frac{2}{4} \times 100 = 50% \]

Thus, the expected percentage of the offspring that is tall is 50%.