Question

Using a Punnett square, workout the distribution of phenotypic features in the first filial generation after a cross between a homozygous female and a heterozygous male for a single locus.

Answer 1

When a heterozygous male tall plant (Tt) crosses with a homozygous dominant female tall plant (TT), we receive two types of gametes in males: half with T and half with t, while females only get one form of gamete, T.

The Punnett square shows that all of the progeny in the F₁ generation are tall (Tt), with 50% homozygous tall (TT) and 50% heterozygous tall (Tt).