Biology for IGCSE & O level - Inheritance (Section 2 - No. 11)

What is the expected genotypic ratio resulting from a monohybrid cross of two heterozygous parents (e.g., Tt x Tt)?

1:1:1:1

1:2:1

3:1

9:3:3:1

The genotypic ratio is the ratio of genotypes. Tt x Tt will produce TT, Tt, and tt in a 1:2:1 ratio