Question

In one of the experiments with pea plants, Mendel observed that when a homozygous tall pea plant (TT) is crossed with a homozygous dwarf pea plant (tt), in the first generation, only tall plants appear. What happens to the traits of the dwarf plant in this case?

Answer 1

When a homozygous tall pea plant (TT) is crossed with a homozygous dwarf pea plant (tt), then the offspring are all tall in height. This happens because allele for tall height (T) is the dominant allele whereas allele for short height (t) is the recessive allele of the same gene.

In the presence of the dominant allele, the recessive allele is not expressed. Hence all the offspring are tall in height since all of them contain the dominant allele (Tt).

Gametes	T	T
t	Tt	Tt
t	Tt	Tt