2.1 HPG Axis

Question 1

Which hormone is released from the hypothalamus to stimulate the HPG axis?

Answer 1

Gonadotrophin releasing hormone (GnRH)

Question 2

Where does GnRH act on?

Answer 2

Anterior pituitary

Question 3

What is released from the anterior pituitary when stimulated by GnRH?

Answer 3

FSH and LH

Question 4

What cells are FSH and LH released from?

Answer 4

Gonadotropes

Question 5

Where do FSH and LH bind to?

Answer 5

Receptors on the gonads

Question 6

Which cells does FSH act on in the male?

Answer 6

Sertoli cells

Question 7

Which cells does FSH act on in the female?

Answer 7

Granulosa cells

Question 8

Which cells does LH act on in the male?

Answer 8

Leydig cells

Question 9

Which cells does LH act on in the female?

Answer 9

Theca cells

Question 10

What effect does FSH and LH have on the ovary?

Answer 10

Controls folliculogenesis
Controls ovulation
Stimulates sex hormone synthesis

Question 11

What effect does FSH and LH have on the testis?

Answer 11

Control spermatogenesis

Sex hormone synthesis

Question 12

What hormone do Leydig cells secrete?

Answer 12

Testosterone

Question 13

What hormone do Sertoli cells secrete?

Answer 13

Inhibin and Androgen Binding Globulin

Question 14

What hormone do Theca cells secrete?

Answer 14

Progesterone

Question 15

What hormone do Granulosa cells secrete?

Answer 15

Oestrogen, Inhibin and Activins

Question 16

What does Inhibin feed back to?

Answer 16

Inhibits levels of FSH

Question 17

How is the male HPG axis restored when testosterone levels are too high?

Answer 17

Negative feedback to the anterior pituitary and hypothalamus