PHYSIOLOGY
REPRODUCTION
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
oestrogen
|
|
|
progesterone
|
|
|
FSH
|
|
|
LH
|
Detailed explanation-1: -When oestrogen rises to a high enough level it causes a surge in LH from the pituitary which causes ovulation where an egg is released from the follicle (Day 14 of the cycle). The follicle becomes the corpus luteum and this produces oestrogen and progesterone which inhibit FSH and LH production by the pituitary.
Detailed explanation-2: -When the level of oestrogen reaches a certain point, it inhibits the release of FSH. This ensures that only one egg develops in each cycle. Oestrogen also stimulates the release of LH from the pituitary gland. LH stimulates an egg to be released from the follicle (ovulation).
Detailed explanation-3: -The ratio of FSH to LH amplitudes decreased in response to estrogen (P = 0.04) indicating a greater sensitivity of FSH than LH to inhibition by estrogen. The inhibitory effect of estrogen on FSH was attenuated with aging (P = 0.02), but was maintained for LH (P = 0.4).