For students With thanks to the TES biologist from whom this was adapted and originally came up with this excellent presentation.

1. What are these basic facts about?
• The cycle is 28 days long
• The breakdown of uterus lining is triggered by low
levels of oestrogen
• Loss of blood and tissue is known as menstruation/
period
• The release of an egg is known as ovulation

2. Mr. Matthews
Tuesday 5 November 2013
The Menstrual Cycle
State the hormones of the menstrual cycle
Understand the basic functions of these
hormones
Explain how these hormones affect the
female reproductive system

3. Hormones
• Four hormones involved in controlling
menstruation
Name
Made…
Function
FSH
Pituitary
Stimulates one egg cell
to develop (become
follicle)
Oestrogen
Follicle (ovary)
Stimulates rebuilding
of the uterus wall
LH
Pituitary
Stimulates follicle to
burst and release the
ovum
Progesterone
Corpus Luteum (ovary)
Completes
development of uterus
wall, promotes
glycogen storage

5. An oocyte (pre-ovum)
surrounded by follicle cells

6. False colour SEM of human uterus wall, approximately 13 days into cycle.
Green cells are secretory, and orange cells are ciliated

8. • Initial concentrations of oestrogen are low.
• The low concentration has a negative
feedback effect on the secretion of FSH.

9. Negative feedback lowers
FSH concentration

11. Positive feedback from
increasing oestrogen
concentration causes
increase in FSH and LH from
pituitary gland.
Follicle gets bigger – releases
more oestrogen

12. • Peak of LH causes follicle to burst and release
ovum
• This is ovulation (on day 14 of the cycle)
• Follicle reforms to become structure called
corpus luteum (‘yellow body’)
• LH stimulates corpus luteum to produce
progesterone.

13. Peak of LH causes ovulation
(day 14)
Oestrogen falls because
follicle is gone, but corpus
luteum still produces some.
Ovulation – ovum released
from follicle. Follicle become
corpus luteum

14. Fall in FSH and LH due to
negative feedback with
oestrogen and progesterone
Progesterone produced by
corpus luteum. Inhibits FSH
and LH
Corpus luteum – produces
progesterone. Uterus wall
fully completed.

15. FSH and LH totally inhibited
Breakdown of corpus luteum
causes fall in progesterone
and oestrogen
Corpus luteum begins to
break down if no embryo has
implanted a week after
ovulation

16. FSH begins to rise since it’s
not inhibited by oestrogen and
progesterone
Low levels of progesterone
and oestrogen because there
is no follicle or corpus luteum
Uterus wall breaks down due
to low levels of oestrogen and
progesterone
New egg cell stimulated by
rising FSH levels