Male & female differentiation of fetus occurs at -

Ans. is 'a' i.e., 10-12 weeks o Gonadogenesis refers formation of gonads, i.e. testes in males and ovaries in females. Genital ridge (urogenital ridge) is the site where gonads develop.o 'Primordial germ cells' are developed in the 4th week by proliferation of endodermal cells of the dorsal wall of hindgut (part of yolk sac). The primordium germ cells migrate into genital ridge, where proliferation of both germinal and nongerminal cells leads to formation of gonads.o Differentiation of genital ridge into lineage of female or male gonads (ovary or testes) occurs at 6-10 weeks.o By 12 weeks this differentiation has occured in all fetuses.