The primary oocytes become surrounded by _____ shortly after their formation; the resulting structure is called a(n) _____. In the adult, hundreds of thousands of these can be observed in the _____; the rest of the original millions have died.

3000+ review questions on anatomy and physiology. 

Anatomy refers to the internal and external structures of the body and their physical relationships, whereas physiology refers to the study of the functions of those structures.