Exam 3: Reproduction Flashcards
Maleness and femaleness characterized in 3 ways:
Genetic sex
Gonadal sex
Phenotypic sex
Genetic sex
XY = male XX = female
Gonadal sex
Males = testes Females = ovaries
Phenotypic sex
External genetalia
Gonads are indifferent/bipotential thru week ___ in fetus
Week 5
Testes begin to develop in weeks
6-7
Ovaries develop in week
9
Genetic sex usually determines
Gonadal sex
Testes cell types
Germ
Sertoli
Leydig
Germ cells produce
Spermatogonia
Sertoli cell synthesize
Antimullerian hormone
Inhibin
Leydig cells synthesize
Testosterone
Ovary cells types
Germ
Theca
Theca + granulosa cells
Germ cells in ovaries produce
Oogonia
Theca cells synthesize
Progesterone
Theca + granulosa cells synthesize
Estrogen
Male internal genital tract
Prostate
Seminal vesicles
Vas deferens
Epididymis
Male external genetalia
Scrotum
Penis
Female internal genital tract
Fallopian tubes
Uterus
Upper 1/3 of vagina
Female external genitalia
Clitoris
Labia major/minor
Lower 2/3 of vagina
Gonadal males have testes that secrete
Antimullerian hormone
Testosterone
**must have both
Wolffian ducts in embryo develop into:
Epididymis
Vas deferent
Seminal vesicles
Ejaculatory ducts
Testosterone stims growth and differentiation of
Wolffian ducts
Antimullerian hormone causes atrophy of
Mullerian ducts
Growth and development of male external genitalia depend on conversion of testosterone to
Dihydrotestosterone and androgen receptors
Gonadal females have ovaries that secrete
Estrogen
Since ovaries don’t produce testosterone ___ are NOT stimulated
Wolffian duct
Mullerian ducts in embryo develop into
Fallopian tubes
Uterus
Upper 1/3 of vagina
Female genitalia does not require ___
Hormones
**growth to normal size requires estrogen
Androgen insensitivity syndrome
Male genotype but female phenotype
Androgen insensitivity syndrome: female who at puberty shows ___ but no ____
Breast development; menstruation
Androgen insensitivity syndrome: pelvic exam reveals
Presence of testes
Short vagina
Androgen insensitivity syndrome reveals no binding of testost. Which means that
Androgen receptors are absent/defective
Androgen insensitivity syndrome has elevated levels of
Testosterone and LH
Patients w/ Androgen insensitivity syndrome do not develop ____
Fallopian tubes
Uterus
Upper vagina
Will never have menstrual cycles/pregnancy
Testes in patients w/ androgen insensitivity syndrome secreted both
Antimullerian hormone and testosterone
- no mullerian ducts
- unresponsive to testosterone
Androgen insensitivity syndrome breast development due to
Testes producing estradiol from testost.
In M and F, gonadal function is driven by
Hypothalamic-pituitary axis
GnRH secretion begins at week ___ of gestation
4
FSH/LH secretion begins btw weeks ___
10-12
FSH and LH levels remain low until
Puberty
FSH>LH
FSH and LH rise during puberty and become ___
Pulsatile
LH >FSH during reproductive period
Old age gonadotropin secretion rate ____
Continues to rise
FSH>LH
Primary hormonal event is initiation of ____ which drives parallel secretion of ______
Pulsatile secretion of GnRH; FSH and LH
FSH and LH stim gonads to produce
Testosterone (M)
Estradiol (F)
____ required for normal reproductive function
Pulsatility
During puberty there are large nocturnal pulses of
LH
GnRH upregulates its own anterior pit receptor which
Inc sensitivity of GnRH receptor
The inc levels of sex steroids during puberty are responsible for
Secondary sexual characteristics
Extreme stress or caloric deprivation may cause
Delayed onset of puberty
____ may play a role in onset of puberty bc of its inhibition of GnRH
Melatonin
Melatonin levels are highest during ____ and dec during ____
Childhood; adulthood
If you remove pineal gland ____ onset of puberty
Earlier (dec melatonin)
Puberty in boys, Leydig cell proliferation causes
Inc synthesis/secretion of testosterone
Puberty in boys the growth of testes is due primarily to inc in number of
Seminiferous tubules (initiate spermatogenesis)
Other changes in puberty in boys
Accessory sex organs grow Growth spurt Pubic/axillary hair Penis growth Voice lowers
Puberty in girls, activation of hypothalamic-pituitary axis drives synthesis of
Estradiol by ovaries
Growth spurt and closure of epiphyseal plates begin/end earlier in
Girls
Appearance of pubic/axillary hair precedes ___ and is dependent on inc secretion of ____
Menarche; adrenal androgens
Testes additional enzyme used to make testosterone
17 B-hydroxysteroid DH
Lack 21 B and 11 B hydroxylase