Changes

Throughout normal sexual development there are series of defined phases;  

Throughout normal sexual development there are series of defined phases;  

===Pregonadal Phase===

===Pregonadal Phase===

The pregonadal phase represents the stage where '''germ cells''' begin to migrate from the yolk sac of the developing embryo. Primitive primordial germ cells are formed in the yolk sac (the yolk sac is part of the digestive system in the embryo). These primitive germ cells migrate from the yolk sac through the mesentry to the '''genital ridges''' which are small elongated pieces of tissue beneath the peritoneum situated at the dorsal aspect of the abdominal cavity.

The pregonadal phase represents the stage where '''germ cells''' begin to migrate from the yolk sac of the developing embryo. Primitive primordial germ cells are formed in the yolk sac (the yolk sac is part of the digestive system in the embryo). These primitive germ cells migrate from the yolk sac through the mesentry to the '''genital ridges''' which are small elongated pieces of tissue beneath the peritoneum situated at the dorsal aspect of the abdominal cavity. These germ cells then begin to divide by mitosis and the gonads are developed from these genital ridges.

===Bipotential Gonadal Phase===

===Bipotential Gonadal Phase===