Question

Question

A tall, heterozygous pea plant (Tt) is crossed with another tall, heterozygous pea plant. Use a Punnett square to determine the probability that the offspring is a short, homozygous pea plant (tt).(1 point)
Responses

0%
0%

50%
50%

75%
75%

25%

Answer 1

To determine the probability of obtaining a short (homozygous recessive) pea plant (tt) from the cross of two heterozygous tall pea plants (Tt), we can use a Punnett square.

1. Set up the Punnett square. The alleles from each parent are placed along the top and the side:

        T      t
      ---------------
   T |   TT   |  Tt  |
      ---------------
   t |   Tt   |  tt  |
      ---------------
   

2. Fill in the Punnett square by combining the alleles from each parent:

   • The top left box shows TT (homozygous tall).
   • The top right box shows Tt (heterozygous tall).
   • The bottom left box shows Tt (heterozygous tall).
   • The bottom right box shows tt (homozygous short).

3. Now, we can tally the results:

   • TT: 1
   • Tt: 2
   • tt: 1

Thus, there are a total of 4 boxes, and 1 of those boxes represents the homozygous recessive genotype (tt).

4. Now calculate the probability:
   • Probability of tt = number of tt boxes / total number of boxes = 1/4 = 25%.

So, the probability that the offspring is a short, homozygous pea plant (tt) is 25%.