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Flashcards in puberty & HPG Deck (42)
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1

define puberty

A stage of human development when sexual maturation and growth are completed and result in ability to reproduce 

2

what determines onset of puberty?

Switching on the HPG axis via hormones!

3

at what stage is the reproductive system active?

at puberty

4

what things occur during puberty

--Maturation of primary sexual characteristics (gonads and genitals)

– Appearance of secondary sexual characteristics (pubic and axillary hair, female breast development, male voice changes,...)

– Menstruation and spermatogenesis begin 

5

environmental influences in puberty?

pineal tumors can influence puberty in humans!

6

In girls, what is the weight set point for puberty, what happens if it falls below this?

critical weight 47 kg

falls below> puberty comes late

7

why does weight effect puberty?

Body weight (Leptins may be involved in signalling )

 

Leptins tied to adipose tissue, they signal the presence of fat in the body!

they interact w/ the hypothalamus and effect the release of GnRH.

 

 


 

8

what hormones do BOTH males and females have before puberty?

testosterone and estrogen,

levels stay fairly constant until puberty!

9

Normal age of puberty in females? males?

9-13 yrs

10-14 years

10

in males and femlaes, pubic hair growth is a response to which hormones? 

TESTOSTERONE!

11

although we females have testosterone, what keeps their levels lower in our body?

we have testosterone binding proteins!

TBP

12

functions of aromatase enzmye?

what inhibits it?

enzyme found in fatty tissue,

 converts testosterone into excess estrogen

 

ZINC

13

functions of estrogen in the growth spurt phase?

  • important in mainting bone mass
  • closing the epiphyseal plate

14

Appearance of secondary sexual characteristics – girls

• 9-13 years
– Breast bud (thelarche)

– Pubic hair growth (T)

 

begins (adrenarche)
– Growth spurt
– Onset of menstrual

 

cycles (menarche) –

Pubic hair adult –

Breasts adul 

15

Appearance of secondary sexual characteristics -boys (testosterone anabolic androgenic steroid 

16

how can we access kids thats r goign through puberty?

and acess what stage theyre in?

TANNER SCALE

17

Genital development in boys depends on?

testosterone

18

the growth spurt is later in males or females?

later in boys!

19

why does somatic growth end earlier in women?

cuz of estrogen>>closes epiphyseal plates earlier

20

 Somatic (body) growth, what does it depend on?

diff btw boys and girls

at what age ta8reeeban do girls stop growing?

boys r later, but rapid, and plates r slower to close!

girls>>16

boys>>18, 19

 

thats why guys faj2a y6ooloon!

21

describe girl/ boy growth pattern from 8-18 yrs

how does it end? in who does it end firsT?

Earlier and shorter in women

Ended in both sexes by epiphyseal fusion

  Oestrogen>> closes epiphyses earlier in girls 

22

Normal Pubertal development 

23

just for extra: why do men get acne?

testosterone causes increased secretion of the body's sebaceous glands, escpecially those on the face!

24

what is responsible for switching this axis on?!

 

GnRH

 

 

25

what gene codes for the GnRH?

what happens if this is blocked?

GnRH -1 gene 

Lack of gonadotrophin synthesis and secretion and reproductive development occurs if GnRH is blocked 

26

how can we treat prepubertal primates?

by giving GnRH gradually

27

what r the characterisitcs of the hypothalamic releasing hormones?

28

describe the HPG axis 

29

what structure in the anterioir pituitary makes LH & FSH?

Gonadotrophs 

which r cells

30

what role does leptin and photoperoid have on the HPG axis?

they interact w/ the hypothalamus and effect the release of GnRH.