7.0 Puberty Flashcards
(39 cards)
What age is average for menarche in females?
13yrs old<br></br><br></br>Usually no egg present (anovulatory)
What is a sign of male puberty?
First ejaculation (often nocturnal)<br></br><br></br>Usually only seminal plasma with no spermatozoa
Define gonadarche:
Changes dependent on steroid hormones from gonads
Define adrenarche:
Changes dependent on steroid hormones from adrenal gland
What age do girls hit peak growth velocity?<br></br>What age do boys hit peak growth velocity?
Girls = 12 yrs<br></br>Boys = 14yrs
What explains the height difference between men and women?
Boys are older and taller at point of take off.<br></br><br></br>Amount grown during growth sprout is actually the same in males and females
Complete the blank:<br></br><br></br>Adult men have _____ times more lean body mass than women.<br></br><br></br>Adult women have _____ times more body fat than men.
Adult men have 1.5 times more lean body mass than women.<br></br><br></br>Adult women have 2 times more body fat than men.
How long after menarche do females experience their first ovulation?
Ranges from months → 2 years
When is adult stature reached in females?
15
When is adult stature reached in males?
17
What do testicular androgens cause in males?
1) Development of genitalia<br></br>2) Body hair<br></br>3) Enlargement of larynx and laryngeal muscles
What do ovarian oestrogens cause in females?
Development of breast and genitalia
What do ovarian and adrenal androgens cause in females?
Pubic + auxillary hair
When do testes descend from abdomen?
7-8th month in utero
What hormones control descent of testes?
1) Mullerian inhibitory substance (MIS)<br></br>2) Testosterone
What directs the pull of testes?
Gubernaculum
When does spermatogenesis begin?
9 yrs
When is mature spermatozoa produced?
14-15yrs
How many ovaries are present at birth?
500,000
How many ovaries are present at puberty?
83,000
What are cryptorchid testes?<br></br><br></br>What is the treatment?
Testes that fail to descend at birth (3-4% of males)<br></br><br></br>0.8% fail to descend by 1 yr<br></br>0.3% fail to descend by 9yrs (commencement of spermatogenesis)<br></br><br></br>Treatment = surgery or Gonadotrophins/GnRH
How much cooler do the testes need to be compared to the body for spermatogenesis?
3.1 degrees
What are the daily patterns of hormone changes seen during puberty in females?
1) Fluctuations<br></br>2) ↑ amplitude (at night then always)
How often do hormonal pulses need to be for puberty to occur?
1-3 hours
Oestradiol
Oestrone
Androgens
Oestrone: body fat
Androgens: adrenal gland
2) Roles in protein synthesis and glucose homeostasis
(other components of system = Neurokinin B + Kisspeptin)
Other pullutants delay male puberty
