Female reproductive system

Question 1

2 functions of ovaries

Answer 1

1) Produce ova (Oogenesis)
2) Secrete oestrogen and progesterone
To promote fertilisation of the ovum and prepare female reproductive tract for pregnancy

Question 2

2 phases in ovarian cycle

Answer 2

Follicular phase and Luteal phase

Question 3

What happens during follicular phase

Answer 3

1) Hypothalamus secretes GnRH (Gonadotropin Releasing Hormone)

2) Anterior pituitary secretes LH and FSH

3) LH and FSH stimulate follicle to secrete Oestrogen
LH stimulates Theca cell + FSH stimulates Granulosa cell → Produce estradiol (a type of oestrogen)
LH and FSH are protein hormones, bind to cell surface receptor

4) Antrum develops (liquid space) to store Oestrogen

5) (-) Moderate level of Oestrogen causes (-) feedback to Hypothalamus and Anterior Pituitary, Developing follicle produces inhibin
Hypothalamus → stop GnRH release
Anterior pituitary → selectively inhibit FSH secretion
Inhibin → selectively inhibit FSH secretion

6) Overall effect: since both Oestrogen and Inhibin selectively inhibit FSH, FSH decreases while LH continues to rise

7) (+) At high level of Oestrogen, Oestrogen acts on hypothalamus to increase GnRH and on pituitary to increase LH (positive feedback)

8) Massive increase in LH secretion causes
Differentiation of follicular cells into luteal cells
Ovulation, release of mature egg

Question 4

Which cells do LH and FSH target?

Answer 4

LH: Theca cells
FSH: Granulosa cells

Question 5

Which cell produces oestrogen?

Answer 5

Granulosa cell

Question 6

What happens during the Luteal phase

Answer 6

1) Corpus Luteum (CL) secretes high levels of Progesterone
(-) Progesterone causes (-) feedback and inhibits GnRH, LH and FSH to get ready for fertilisation + prevent new follicular maturation and ovulation

2) If there is no fertilisation, Corpus Luteum degenerates, no Oestrogen and Progesterone produced → Negative feedback inhibited

3) New follicular phase begins

Question 7

3 phases of Menstruation

Answer 7

Menstrual phase
Breakdown of endometrium
Very low Oestrogen and Progesterone

Proliferative phase
Oestrogen rises, causing thickening of endometrium
Ovulation occurs

Secretory phase
Progesterone rises, increasing no. of blood vessels and secretory glands

Question 8

Why does menopause occur

Answer 8

Ovaries become less responsive to LH and FSH, secrete less estrogen and progesterone

Question 9

Meaning of
Amenorrhea
Dysmenorrhea
Menorrhagia
Metorrhagia

Answer 9

Amenorrhea → lack of menstrual bleeding
Eg. Turner’s syndrome (non working ovaries)
No onset of menstrual periods by 16

Dysmenorrhea (pain)

Menorrhagia (too much bleeding) and

Metrorrhagia (bleeding other than period)

Question 10

2 roles of LH during Follicular phase

Answer 10

1) Follicle growth and maturation
2) Induce antrum formation