Puberty

Question 1

What is puberty

Answer 1

Puberty - stage of human development when sexual maturation and growth are completed

Question 2

What changes are there in females during puberty

Answer 2

Thelarche - breast bud development

Pubic hair growth - becomes coarser after menarche

Adrenarche - causes growth spurt and onset of menstral cycle

Menarche

Question 3

What changes are there in males during puberty

Answer 3

Genital development

Pubic hair growth

Spermatogenesis begins

Growth spurt

Question 4

What is the name for early puberty

Answer 4

Pernicious puberty

Question 5

Why do males generally have a longer growth spurt than females

Answer 5

Testosterone produced by males causes the longer growth spurt

Oestrogen causes closure of epiphyseal growth plates -> stops growth - females have higher concentration of oestrogen -> do not grow much

Question 6

How is GnRH secreted and what does it stimulate

Answer 6

Secretion of GnRH is in pulses

GnRH stimulates:

• Release of stored pituitary hormones
• Synthesis of pituitary hormones
• Hyperplasia and hypertrophy of receptor cells
• Acts to regulate its own receptor

Question 7

How is testosterone production stimulated

Answer 7

Testosterone production is stimulated by LH

LH stimulates Leydig cells in the testis to produce testosterone from cholesterol

Question 8

Describe the production of testosterone - rhythm and when it is highest

Answer 8

Testosterone is under circadian rhythm of secretion

Highest levels are in the morning

Question 9

Where are leydig cells found

Answer 9

In the interstitium

Question 10

What are the functions of sertoli cellsq

Answer 10

Provide nutrition and hormonal support to germ cells

Allows sperm formation

Question 11

What is the effect of FSH on sertoli cells

Answer 11

FSH causes increased production of sperm

Question 12

What hormone do sertoli cells produce and what is its function

Answer 12

Sertoli cells secrete inhibin

Inhibits release of FSH

Allows for volume control to prevent excessive sperm production

Question 13

What effect do FSH and LH have in the ovaries

Answer 13

Stimulate sex hormone synthesis

Control gamete production

Question 14

Which cells in the ovary respond to FSH and which respond to LH

Answer 14

Granulosa cells respond to FSH

Theca interna cells respond to LH

Question 15

How does the concentration of oestrogen affect GnRH secretion

Answer 15

Moderate oestrogen levels inhibits GnRH secretion

High oestrogen levels promotes GnRH secretion to cause an LH surge

Question 16

How does progesterone affect oestrogen’s function

Answer 16

Progesterone increases inhibitory effects of moderate levels of oestrogen -> inhibits GnRH

Progesterone prevents positive feedback of high levels of oestrogen

Question 17

What cells in the ovary produce inhibin

Answer 17

Granulosa cells of corpus luteum

Question 18

How does GH secretion cause a growth spurt

Answer 18

GH increases TSH levels

GH increases metabolic rate

GH promotes tissue growth

GH increases androgen production -> causes retention of minerals to support bone and muscle growth