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?
a 0%
b 25%
c 50%
d 75%

Answer 1

To solve this problem, we need to set up a Punnett square using the genotypes of the parent plants:

- The heterozygous tall pea plant has the genotype Tt.
- The homozygous recessive short pea plant has the genotype tt.

When we cross these two plants, the possible combinations of their alleles are:

- From the Tt parent, the alleles could be either T (tall) or t (short).
- From the tt parent, the alleles will always be t (short).

Now we can set up the Punnett square:

| | t | t |
|-------|-------|-------|
| **T** | Tt | Tt |
| **t** | tt | tt |

From the Punnett square, we can see that the possible offspring genotypes are:
- 2 Tt (tall)
- 2 tt (short)

Now we can calculate the percentages:
- 2 out of 4 offspring (or 50%) are expected to be tall (Tt).
- 2 out of 4 offspring (or 50%) are expected to be short (tt).

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

The correct answer is:
**c 50%**