Question

In the XX–XY sex determination system, which sex is considered heterogametic and produces two different types of gametes?

Options

• Males with XY genotype

• Females with XX genotype

• Both males and females

• Neither males nor females

Answer 1

In the XX–XY system found in humans and Drosophila, males with XY genotype are heterogametic, producing two types of sperm: X-bearing sperm and Y-bearing sperm. Females with XX genotype are homogametic, producing only X-bearing eggs. The male gamete determines the sex of the offspring.