Control of the menstrual cycle

Question 1

Which 4 hormones control the menstrual cycle?

Answer 1

oestrogen, progesterone, FSH, and LH

Question 2

What effect does oestrogen have?

Answer 2

targets the ovaries

repairs, maintains, thickens the lining of the uterus

stops FSH being produced
stimulates the pituitary gland to release LH

Question 3

What effect does progesterone have?

Answer 3

secreted from the corpus luteum

maintains the lining of the uterus

inhibits FSH and LH

Question 4

What effect does LH have?

Answer 4

ovulation

a mature egg is released from a follicle

Question 5

What effect does FSH have?

Answer 5

causes a follicle in the ovary to mature

stimulates the ovaries to release oestrogen

Question 6

Explain how FSH, LH, oestrogen and progesterone interact to control the menstrual cycle.

Answer 6

FSH is secreted from the pituitary gland.
This causes a follicle in the ovary to mature.
The production of oestrogen is also stimulated, it is secreted from the follicle.

the oestrogen inhibits FSH
starts to thicken the lining of the uterus
stimulates a surge of LH from the pituitary gland

LH causes ovulation, a mature egg is released from the follicle
the ruptured follicle becomes a copus luteum which secretes progesterone and some oestrogen
(day 14)

the uterus lining thickens further
progesterone inhibits FSH and LH
if the egg isn’t fertilised, the corpus luteum breaks down, and the concentration of progesterone falls
(from day 14)

menstruation is triggered when all the hormone levels are low / oestrogen and progesterone levels fall

as FSH is no longer inhibited, it can be secreted from the pituitary gland again

Question 7

What happens to hormone levels if a women becomes pregnant?

Answer 7

the placenta produces progesterone so the lining of the uterus is maintained during pregnancy

Question 8

Where are the following hormones made in the human body?

a) oestrogen and progesterone
b) FSH and LH

Answer 8

a) in the ovaries

b) in the pituitary gland

Question 9

Describe the hormonal changes that cause menstruation

Answer 9

fall in oestrogen and progesterone levels

Question 10

Give the role of the following hormones in the menstrual cycle:

a) oestrogen
b) progesterone
c) FSH
d) LH

Answer 10

a) thickening of uterus wall and triggering of LH release
b) thickening of uterus wall
c) stimulates growth and development of egg in ovary
d) triggers ovulation