Flashcards in 7.0 Puberty Deck (39)
What age is average for menarche in females?
Usually no egg present (anovulatory)
What is a sign of male puberty?
First ejaculation (often nocturnal)
Usually only seminal plasma with no spermatozoa
Changes dependent on steroid hormones from gonads
Changes dependent on steroid hormones from adrenal gland
What age do girls hit peak growth velocity?
What age do boys hit peak growth velocity?
Girls = 12 yrs
Boys = 14yrs
What explains the height difference between men and women?
Boys are older and taller at point of take off.
Amount grown during growth sprout is actually the same in males and females
Complete the blank:
Adult men have _____ times more lean body mass than women.
Adult women have _____ times more body fat than men.
Adult men have 1.5 times more lean body mass than women.
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?
When is adult stature reached in males?
What do testicular androgens cause in males?
1) Development of genitalia
2) Body hair
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)
What directs the pull of testes?
When does spermatogenesis begin?
When is mature spermatozoa produced?
How many ovaries are present at birth?
How many ovaries are present at puberty?
What are cryptorchid testes?
What is the treatment?
Testes that fail to descend at birth (3-4% of males)
0.8% fail to descend by 1 yr
0.3% fail to descend by 9yrs (commencement of spermatogenesis)
Treatment = surgery or Gonadotrophins/GnRH
How much cooler do the testes need to be compared to the body for spermatogenesis?
What are the daily patterns of hormone changes seen during puberty in females?
2) ↑ amplitude (at night then always)
How often do hormonal pulses need to be for puberty to occur?
What is the first endocrine change to occur in puberty?
Where are the following released from in females?
Oestradiol: follicles in ovary
Oestrone: body fat
Androgens: adrenal gland
What is the source of oestrogens in males?
What causes acne?
Androgens → ↑ sebum → clogged glands → acne
What is the effect of growth hormone during puberty?
1) Increases bone and tissue growth (along with androgens)
2) Roles in protein synthesis and glucose homeostasis