2.2 Hormonal Control Of Reproduction

Question 1

In males, hypothalamus secrets a hormone which causes the pituitary gland to produce what two hormones?

Answer 1

FSH- follicle stimulating hormone

ICSH- interstitial cell stimulating hormone

Question 2

In women, hypothalamus secrets a hormone which causes the pituitary gland to produce what two hormones?

Answer 2

FSH- follicle stimulating hormone

LH - lutenising hormone

Question 3

FSH in males

Answer 3

Promotes sperm production in seminiferous tubules

Question 4

ICSH in males

Answer 4

Stimulates interstitial cells to produce testosterone

Question 5

FSH in women

Answer 5

Stimulates development & maturation of each follicle

Stimulates ovary to secrete oestrogen

Question 6

LH in women

Answer 6

Triggers ovulation & brings about development of corpus luteum to secrete progesterone

Question 7

What does the male sex hormone testosterone do?

Answer 7

Stimulates sperm production and activates seminal vesicles and prostate gland to produce secretions

Question 8

What is negative feedback control in men?

Answer 8

Testosterone conc builds up & reaches a level which inhibits secretion of FSH & ICSH
Then leads to a decrease in testosterone conc & pituitary gland releases FSH & ICSH again

Question 9

What does Oestrogen stimulate?

Answer 9

Stimulates proliferation of endometrium to prepare uterus for embryo

Question 10

Highest conc of oestrogen is just before ovulation what does it stimulate then?

Answer 10

Stimulates cervix to secrete a thinner and watery mucus that can be penetrated by sperm
Also LH by pituitary gland

Question 11

What does progesterone do?

Answer 11

Promotes further development & vascularisation of endometrium to form a spongy layer made of blood vessels to prepare for embryo
Also inhibits FSH & LH by pituitary gland

Question 12

How long does a mensural cycle last and what are the stages?

Answer 12

Lasts 28 days 
Follicular phase (1-14)
Luteal phase (14-28)

Question 13

What does pituitary gland do during follicular phase?

Answer 13

Releases FSH which brings about development of follicle & production of oestrogen by ovarian tissue

Question 14

What happens to concentration of oestrogen in follicular phase?

Answer 14

Builds up and brings about repair & proliferation of endometrium
Also triggers surge in LH & FSH around day 14 which causes ovulation

Question 15

How long does egg move down oviduct before fertilisation can occur?

Answer 15

3-4 days

Question 16

During Luteal phase corpus luteum secretes progesterone & oestrogen which inhibits

Answer 16

Production of LH & FSH & If fertilisation doesn’t occur lack of LH degenerates corpus luteum which leads to rapid drop in progesterone & oestrogen & menstruation begins

Question 17

What hormone does embryo secrete if fertilisation occurs?

Answer 17

HCG- human chronic gonadotropin which has same effect as LH

Question 18

What does HCG do?

Answer 18

Maintains corpus luteum & secretes progesterone & also prevents menstration.

Question 19

After 6 weeks placenta takes over to secrete

Answer 19

Progesterone