Puberty & HPG axis

Question 1

What age do females start puberty?

Answer 1

9-13 years old

Question 2

What is the first sign of female puberty?

Answer 2

Breast buds (thelarche)

Question 3

What age do males start puberty?

Answer 3

10-14 years old

Question 4

What is the first sign of male puberty?

Answer 4

Genital development

Question 5

What is the tanner scale?

Answer 5

Used to assess the stage of puberty

Question 6

What causes epiphyseal plates to close?

Answer 6

Oestrogen

Question 7

What is the critical weight for girls to start puberty?

Answer 7

47kg

Question 8

What starts puberty?

Answer 8

Nocturnal release of pulsatile GnRH from the hypothalamus

Question 9

How many peptide hormones does the anterior pituitary produce?

Answer 9

6

Question 10

GnRH stimulates the anterior pituitary to produce what?

Answer 10

FSH and LH

Question 11

How often is GnRH released?

Answer 11

Every 1-3 hours

Question 12

What does LH do in males?

Answer 12

Stimulates Leydig cells to produce testosterone

Question 13

Where are the Leydig cells in the testes?

Answer 13

In the interstitium around the seminiferous tubules

Question 14

What do sertoli cells in the testes do?

Answer 14

Provide nutrition and hormonal support to germ cells to form sperm

Question 15

Which cells in the female respond to FSH?

Answer 15

Granulosa cells

Question 16

Which cells in the female respond to LH?

Answer 16

Theca cells

Question 17

What is the feedback on GnRH in females?

Answer 17

Moderate oestrogen = negative feedback, High oestrogen = positive feedback (LH surge)

Question 18

What does progesterone do to FSH and LH?

Answer 18

prevents positive feedback of high oestrogen preventing LH surge, increases inhibitory effect of moderate oestrogen. REDUCES GnRH, NO LH surge

Question 19

What does Inhibin do to FSH?

Answer 19

Inhibits secretion

Question 20

What does Leptin do?

Answer 20

It is the energy status of the bodies capability to maintain a pregnancy. Can regulate GnRH