Category: Everyday Science | Last updated: 2026-09-18

In a Punnett square, if both parents are heterozygous (Aa), what is the probability of a homozygous recessive (aa) offspring?

A) 0%

B) 25%

C) 50%

D) 75%

Explanation

Aa × Aa cross produces: AA (25%), Aa (50%), aa (25%). The chance of homozygous recessive (aa) is 25%.