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%**.