Lecture Notes: Sexual Differentiation, Sex Determination, and Gametogenesis
2. Sex Determination
2.1. Genetic (Chromosomal) Sex
· Determined at fertilization when the embryo receives either:
o 46,XX → Genetic Female
o 46,XY → Genetic Male
· This initial event determines whether the gonads will develop as testes or ovaries
· The presence or absence of the Y chromosome is pivotal.