Sexual development Flashcards
Menstrual cycle fill in the gaps:
At the start of the menstrual cycle ______ levels are low and progesterone levels are very _______.
The ______ ______ secretes small amounts of FSH and LH in response to _______.
During the ______ phase in the ovary, several follicles begin to grow in response to FSH. Follicle cells have receptors for FSH but not ______ at this stage.
At the start of the menstrual cycle oestrogen levels are low and progesterone levels are very low.
The anterior pituitary secretes small amounts of FSH and LH in response to GnRH.
During the follicular phase in the ovary, several follicles begin to grow in response to FSH. Follicle cells have receptors for FSH but not LH at this stage.
Menstrual cycle fill in the gaps:
As the follicle grows, it secretes ________, causing the lining of the uterus to proliferate and thicken.
_________ levels remain low since oestrogen and _______ feedback to the hypothalamus to inhibit FSH and LH.
The follicle increases in size until it produces high levels of ________. The peak is around _____ days. This stimulates (rather than inhibits) production of GnRH by the hypothalamus. This is ______ feedback.
There is a _________ in FSH and LH.
As the follicle grows, it secretes oestrogen, causing the lining of the uterus to proliferate and thicken.
Oestrogen levels remain low since oestrogen and inhibin feedback to the hypothalamus to inhibit FSH and LH.
The follicle increases in size until it produces high levels of oestrogen. The peak is around 10-14 days. This stimulates (rather than inhibits) production of GnRH by the hypothalamus. This is positive feedback.
There is a sharp rise in FSH and LH.
Menstrual cycle fill in the gaps:
After the sharp rise in FSH and LH, the follicle now has receptors for ______.
In response to the rise in LH, the ________ completes its _________ division, producing a _______ oocyte and a ________.
Ovulation occurs ___ day(s) after the LH surge.
After the sharp rise in FSH and LH, the follicle now has receptors for LH.
In response to the rise in LH, the primary oocyte completes its first meiotic division, becoming a secondary oocyte and a small polar body.
Ovulation occurs one day after the LH surge.
Menstrual cycle fill in the gaps:
After the secondary oocyte and small polar body have been formed, the ovary enters the _____ phase.
LH stimulates leftover follicle cells to form a _______. Under the influence of LH, this secretes oestrogen and _________. Up until now, _________ levels were very low.
During this phase, combined levels of oestrogen and ______ inhibit FSH and LH production, preventing more follicles from developing.
After the secondary oocyte and small polar body have been formed, the ovary enters the luteal phase.
LH stimulates leftover follicle cells to form a corpus luteum. Under the influence of LH, this secretes oestrogen and progesterone. Up until now, progesterone levels were very low.
During this phase, combined levels of oestrogen and progesterone inhibit FSH and LH production, preventing more follicles from developing.
Menstrual cycle fill in the gaps:
Progesterone enables uterus to prepare for ________ and provides endometrium layer with a good blood supply and ________-rich fluid secreted from glands in case an egg is fertilised.
Progesterone levels peak around day ____
Progesterone enables uterus to prepare for implantation and provides endometrium layer with a good blood supply, glycogen rich fluid secreted from glands in case an egg is fertilised.
Progesterone levels peak around day 22
