Puberty Flashcards
what is adrenarche?
increase in DHEA and DHEAS
cellular remodelling of the adrenals to form the zona reticularis - allows adrenal androgen secretion
what is pubarche?
growth of pubic and axillary growth due to the presence of adrenal androgens in adrenarche
assosiated with increased sebum and abnormal keritinisation
what is gonadarche?
usually follows gonadarche
activation of steroids allowing the production of cable gametes
what is the difference between gonadarche in males and females?
males have instantly active gametes
females take approximately 1 yr of aovulatory cycles to be activated
what is thelarche?
development of breast tissue
how does the activity of the HPG change?
active from 16w GA to 1-2 yrs then reactivated at puberty prepubertal nocturnal GnRH highest levels in mid to late puberty becomes pulsatile in adulthood - with no nocturnal patterns
what is the role of kisspeptin in GnRH regulation?
GPR54 receptors on the GnRH neurones in the hypothalamus
what occurs if there is a lack of GPR54 receptors?
the HPG is not active - so there is hypogonadotrophic hypogonadism
what happens if there is an activation mutation of the HPG?
precocious puberty
what are the development of pilosebacous units?
villous PSU are fine hair
differentiate into terminal PSUs - beard
OR apo-PSUs - pubic and axillary hair
what is consonance?
ordered and smooth progression through the pubertal stages
varies in time pace and age, but the order remains the same
what happens if there is a lack of consonance?
there is a pubertal disorder
what is the physiology of the adolescent growth spurt?
occurs due to high GH in balance with oestrogen
low in oestrogen - linear growth and bone maturation
high oestrogen causes fusing of the epiphyseal plates
if there is precousios puberty there is early fusion
occurs 2 yrs early in girls
what is the maximum growth velocity for girls vs boys>
9cm/yr in girls - peaks at 12
10.3/yr in boys - peaks at 14
what is menarche?
development of periods- doesn’t mean they are fertilise
average 12.5 yrs – decreased over yrs due to increased nourishment
what psychological changes occur in puberty?
neuronal remodelling means increased need fro independance, increased sexual awareness, development of sexual personality
later the onset, the better the adjustment
what effect does oestrogen secretion have?
breast development and growht
uterus enlargement, cytology changes and secretions
what effect does testosterone have on sexual maturation?
penile and scrotal development
what effect does FSH secretion have on sexual maturation?
testicular enlargement and follicle developmetn
what effect does adrenal androgens have on sexual development?
pubic and axillary hair growth
what effect dies sex steroid and GH secretion have on sexual maturatoin
cause the growth spurt
what happens with oestrogen removal in sexual development?
aovulutory menarche
what happens when there is introduction of the LH surge?
ovulatory menarche begins
what effect do androgens have on sexual develometn?
enlargement of the larynx - adams apple formation - voice deepens
