What is vitellogenesis and where does it occur a)primary oocyte in graafian follicle b)secondary oocyte in fallopian tube

(a)Primary oocyte in Graaphian Follicle

During growth phase of oogenesis, an egg nest forms ovarian follicle (Graafian follicle) one central oogonium grows and functions as primary oocyte. The others form the covering follicular cells. The later provide nourishment to primary oocyte. Yolk is deposited in this state. This phenomenon is called vitellogenesis.