Reproductive System Flashcards
What are oocytes?
Oocytes are germ cells that eventually undergo meiosis to become a mature ovum ready for fertilisation.
Primordial follicles each contain a primary oocyte, how do primordial follicles become the primary follicles?
Primordial follicles grow and become the primary follicle, the primary follicle has 3 layers: primary oocyte in the centre, the ZONA pellucida and the cuboidal shaped granulosa cells.
What do the granulosa cells secrete?
They secrete the material that becomes the Zona pellucida and also secrete oestrogen.
What happens to the follicles as they grow larger?
As the follicles grow larger, they develop a further surrounding layer called the theca follicular, the inner layer of the theca follicular is called theca interna which secretes androgens, while the outer layer is called theca externa which is made up of connective tissue containing smooth muscle and collagen.
How does ovulation occur?
When there is a surge of LH from the pituitary, this causes the smooth muscle of the theca externa to squeeze and cause the follicle to burst. Follicular cells also release digestive en homes which puncture a hole in the wall of the ovary and allow the ovum to escape. The oocyte is released into the area surrounding the ovary and at this point is free floating in the peritoneal cavity before being quickly swept up by the fimbrae.
How long does the corpus luteum degenerate after if not fertilised?
10–14 days
