Question

a homozygous tall pea plant (tt) is crossed with a heterozygous tall pea plant (tt). which statement is true about the offspring of this cross?
all of the offspring will have the same phenotype (short), but two different genotypes (tt, tt)
all of the offspring will have the same phenotype (short) and the same genotype (tt).
all of the offspring will have the same phenotype (tall), but two different genotypes (tt, tt)
all of the offspring will have the same phenotype (tall) and the same genotype (tt).

Explanation:

When a homozygous tall pea plant (TT) is crossed with a heterozygous tall pea plant (Tt), the possible genotypes of the offspring are determined by the following cross:

• The homozygous tall plant (TT) can only contribute a T allele.
• The heterozygous tall plant (Tt) can contribute either a T or a t allele.

Using a Punnett square:

	T	T
t	Tt	Tt

The genotypes of the offspring are TT and Tt. Since the T allele is dominant for the tall trait, both TT and Tt genotypes will result in the tall phenotype.

Answer:

All of the offspring will have the same phenotype (tall), but two different genotypes (TT, Tt)