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Flashcards in Puberty Deck (55)
1

Adrenarche

Activation of adrenal cortex for the production of adrenal androgens, and typically occurs before the onset of puberty. Leads to pubarche (pubic and axillary hair growth) and doesn't require gonads.

2

Gonadarche

Activation of the gonads by the pituitary hormones FSH and LH and sex steroid secretion. Leads to thelarche (breast dev) and sexual maturation. Does not require the adrenal gland

3

Menarche

Age of onset of first menstural period

4

Where is DHEAS produced?

During andrenarche, the adrenal gland's zona reticularis produces DHEAS

5

Is adrenarche under direct control of ACTH/cortisol?

NO, has nothing to do with the gonads

6

What stimulates gonadarche

Onset of GnRH pulsitility

7

What usually comes first, thelarche or pubarche?

Thelarche, though in 8-15% of girls, pubarche occurs first

8

What causes breast dev?

Estrogen production by ovaries

9

Breast Tanner stage I

Prepubertal

10

Breast Tanner stage II

Breast bud forms, areola erect (11.2 y.o)

11

Breast Tanner stage III

Breast tissue enlarges beyond areola (12.2)

12

Breast Tanner stage IV

Areola and papilla form second mound (13.1y.o)

13

Breast Tanner stage V

Adult breast: areola and breast tissue same plane, papilla erect (15.3 y.o)

14

Limitations to Tanner staging

-Based off of limited pop
-Dif ethnicities=dif ages

(note seq of events is the same)

15

Normal breast dev occurs at a younger age in...

African Americans than in Whites

16

What age range of breast dev req further evaluation of any girl?

Dev at age 13

17

Which enzymes initiate adrenarche

P450c17 which inc DHEA, DHEA-s, androstenedione

18

How many years before the appearance of secondary sex charac does adrenarche occur?

2

19

What is adrenarche responsible for

Pubarche

20

Does andrenarche play a role in skeletal growth?

Not really

21

What is the relationship between adrenarche and gonadarche?

They are temporally related, but independent, functionally unrelated biologic events

22

F. Pubic Tanner stage I

Pre pubertal, no pubic hair

23

F. Pubic Tanner stage II

Coarse, curly, pigmented hair laterally (11.7)

24

F. Pubic Tanner stage III

Coarse, curly hair spread across pubis (12)

25

F. Pubic Tanner stage IV

Abundant adult pubic hair, limited to pubis (13)

26

F. Pubic Tanner stage V

Pubic hair present on medial thigh (14)

27

What race does pubarche usually occur in first

African American ealier than white

28

When does menarche occur?

Once there is sufficient gonadal estrogen, secretion occurs and the endometrial proliferation occurs. First period is not necessarily associated with ovulation. Postmenarcheal cycles are initially anovulatory. Sustained predictable LH surge responses to estradiol with ovulation are late pubertal events. Can be anovulatory for even 5 years.

29

How long after breast dev does menarche occur

approx 2 years

30

Why do we think age at menarche is dec?

Better nutritional status, improved standards of living

31

M. Pubic Tanner I

Preadolescent (Testis and Penis)

32

M. Pubic Tanner II

P: slight enlargement, T: enlarged scrotum, pink, texture rough

33

M. Pubic Tanner III

P: inc length
T: inc size

34

M. Pubic Tanner IV

P: Glans enlarged, inc breadth
T: enlarged darker color

35

M. Pubic Tanner V

Adult size (P and T)

36

At what age and tanner stage does spermatogenesis first start?

11-15 y.o, Tanner 2-3

37

What is the mean age of first conscious ejaculation?

13.5

38

Growth spurt dep on what hormone?

IGF-1 and sex sterioids

39

What initially causes long bone growth in girls

Estrogen

40

Descibe changes in genitalia in girls

-Vag length increases
-Labia become thick and rugated (minora first)
-Adipose tissue appears in mons pubis
-clit enlarges
-Vag mucosa becomes less shiny and thicker

41

Describe chanegs in genitalia boys

-Testes inc in size
-Sertoli cells stop mitosis
-Germ cells predominate
-Leydig cells develop
-Spermatogenesis occurs
-Penis enlarges
-Ejac occurs

42

How many years after girls is boys growth spurt

About 2 years

43

Describe gonadotropin levels in the neonatal pd

-High after birth up to 2 years
-Release of suppression from maternal E and P when born and umbil cord clamped
-Transient E or T sec induced by high FSH/LH at this time leading to dev of ovarian cysts in females

44

Describe gonadotropin levels in childhood

-FSH, LH levels suppressed
-E and T suppressed
-Low level pulses of GnRH (not due to neg feedback since that is suppressed)

45

What initiates puberty

Pulsatile GnRH is responsible for gonadarche

Evidence: pit and gonads dont limit gonadarche, GnRH can stim puberty

46

What is happening to follicles in childhood

Dev but only to antral stage (pre-gonadotropin dep stage)

47

Why is LH a marker for GnRH but FSH is not?

LH has a shorter half life so its levels mirror GnRH pulsatility

48

Describe LH in males during puberty

Initial sign of puberty is high LH pulse at night

49

Mid-puberty

is when sufficent gondal estrogen is secreted to proliferate endometrium and allow menarche

50

How long are cycles usually anovulatory for

First 1-2 years

51

What is the first gross sign of pub in males

Growth of testes

52

The inhibition on the hypothalamus during childhood is...

intrinsic, agonadal children have same FSH/LH suppression pre puberty

53

List some factors that may influence the onset of puberty/turn on hypothal

-Genetic (sisters and mom have similar age of onset)
-Environment (less phys activity, better nut, urban environment)
-epitgenetics (
-Toxic exposure (BPH)
-Nutritional status (fat can produce estrogen, delayed in malnurished)
-Hormonal factors (in meats

54

What are some theories as to what triggers release on GnRH after childhood?

-GABA is inhibiting GnRH in female via a GnRH receptor
-NPY: inhibits GnRH in males via hypothal receptor
-Leptin: Receptors on hyppothal and ant pit, inc during childhood until puberty. Necessary in a permissive role for gonadarche to occur.
-Kisspeptin:

55

What is the leading theory today?

Kisspeptin: Inc just before pub, may come together with estrogen to stimulate GnRH release and begin puberty