Biology 30: Reproduction

Female Reproductive SystemAnatomy:

Hormones & Feedback: GnRH – stimulates the release of the gonad targeting pituitary hormonesFSH – stimulates the follicle to develop in the ovary, follicle then produces estrogenEstrogen – produced by the follicle, negatively feeds back for FSH and positively for LH. Maintains the endometrium and development of secondary sex characteristics. Also produced later by the corpus luteum.LH – stimulates the follicle for ovulation to occur and then development of the corpus luteumProgesterone – produced by the corpus luteum. Maintains endometrium & negatively feeds back to pituitary.

Phases of the Menstrual Cycle:Phase Events Hormones DaysFlow Menstruation FSH begins to rise, all others very low 1-5

Follicular Follicle develops in ovary, endometrium builds

FSH high, Estrogen produced by follicle 6-13

Ovulation Oocyte bursts from ovary Caused by a spike in LH 14

Luteal Corpus luteum forms, endometrium thickens

Estrogen and progesterone produced by C.L. 15-28

FOLLICULAR – Days 6-13