Physiology 3120 Lecture Notes - Lecture 2: Pregnenolone, Cholesterol Side-Chain Cleavage Enzyme, Activin And Inhibin

• School: Western University
• Department: Physiology
• Course: Physiology 3120
• Professor: Tom Stavraky

Document Summary

So left has follicle that develops into ovum. To get to that stage, require gnrh to stimulate fsh/lh production. In case of twins, rare event where two follicles reach ovulation. Cycle has two ovarian phases follicular ie: follicle growth until ovulation and luteal ie: corpus luteum regression. Proliferative phase involves endometrium buildup under influence of estrogen produced by developing follicle. Secretory phase involves differentiation of cells to become secretory cells under influence of progesterone. Secretions into uterine lining to prepare for implantation. If no implantation, hormone levels drop so cells no longer maintain differentiation/secretion and corpus luteum regresses. Menstruation occurs with sloughing off of endometrial layer, making endometrium thinner before entering next follicular phase. Lh surge causes ovulation to leave behind corpus luteum. Granulosa cells are female equivalent of male sertoli cells line oocyte and provide nourishment through their metabolism to oocyte. Granulosa cells secrete glycoproteins to form zona pellucida surrounding oocyte.