Question

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.

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

(1 point)
Responses

25%
25%

0%
0%

50%
50%

75%

Answer 1

To determine the percentage of tall offspring from a cross between a heterozygous tall pea plant (Tt) and a homozygous recessive short pea plant (tt), we can set up a Punnett square.

1. **Parent Genotypes**:
- Parent 1 (heterozygous tall): Tt
- Parent 2 (homozygous recessive short): tt

2. **Possible Gametes** from each parent:
- Parent 1 can produce gametes: T or t
- Parent 2 can produce gametes: t or t

3. **Punnett Square**:
```
T | t
------------------
t | Tt | tt
------------------
t | Tt | tt
```

4. **Offspring Genotypes**:
- Tt (tall): 2 squares
- tt (short): 2 squares

5. **Percentage Calculation**:
- Total offspring: 4 (2 Tt + 2 tt)
- Tall offspring (Tt): 2 out of 4

Thus, the percentage of tall offspring is:
\[
\frac{2}{4} \times 100 = 50\%
\]

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