Describe the role or each of the following hormones in the human menstrual cycle
(i) Oestrogen
(ii) Progesterone
(iii) Luteinising hormone

Answer:

(i) Oestrogen
-Oestrogen causes repair/healing of uterine wall
-Oestrogen stimulates anterior lobe of pituitary to produce luteinising hormone (LH)

(ii) Progesterone
-Progesterone causes proliferation/thickening of uterine wall
-Stimulates increased blood supply to the endometrium
-Inhibits the production of follicle stimulating hormone (FSH)

(iii) Luteinising hormone
-LH causes ovulation.
-It also causes graafian follicle to change into corpus luteum.
-LH stimulates corpus luteum to secrete progesterone

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