Question

In the ZW–ZZ sex determination system, which sex is heterogametic?

Options

• Neither males nor females

• Both males and females equally

• Females with ZW genotype

• Males with ZZ genotype

Answer 1

In the ZW–ZZ system, females with ZW genotype are heterogametic and produce two types of eggs: Z-bearing and W-bearing eggs. This contrasts with the XX–XY system where males are heterogametic. Males with ZZ genotype are homogametic, producing only Z-bearing sperm.