p+b 2 sexual diff and steroid hormones

androgens

secretes from testes in men and adrenal gland in men and women

estrogen/projesterone

secreted from ovaries in females and adrenal gland in males and females

HPG axis

hypothalamus pituitary gland axis, hypothalamus regulates testes and ovaries through pituitary gland

male HPG axis

GnRH from hypothalamus stimulates pituitary to send FSH and LH to the testes

FSH stimulates sperm production

LH stimulates testosterone release

if testosterone levels are too high, shuts off production of FSH and LH

female HPG axis follicular phase

GnRH stimulates anterior pituitary to make FSH, which grows and matures the follicle in the ovaries, and stimulates estrogen secretion slowly from the ovaries

female HPG axis: ovulation

rising estrogen levels create LH surge and inhibit FSH, follicle breaks and produces egg and corpus luteum, which creates estrogen and projesterone

female HPG axis: luteal phase

need high progesterone to keep fertilized egg healthy, so progesterone inhibits LH production (because it would shut it down) and the placenta takes over pituitary jobs, creates more estrogen and progesterone from ovaries

birth controls

morning after/abortion: progesterone blockers, no progesterone= contractions

birth control pills: estrogen and progesterone, stops LB and FSH production

organization vs activational effects

organizational, early in life and long lasting external and internal sex organs brain structure and reproductive/nonreproductive behaviors

activational: puberty, dependent on organization effects of hormones

XY sexual diff

female is default, Y antigen promotes development of testes, which start to create testosterone at 12 weeks, then outward genitalia is masculinized, fully complete at birth

5α reductase deficiency

genetic males do not have enough of the enzyme that converts testosterone to 5a DHT which is what the body actually uses, so not enough to fully masculinized genitalia

congenital adrenogenital syndrome

genetic female fetus exposed to too much androgens from adrenal cortex masculinized genitalia

wolffian system

male, develops under influence of testicular testosterone, epdidymus vas deferens seminal vesicle prostate

if no testosterone, the wolffian system atrophies

mullerian system

female, develops without influence of any hormones into fallopian tubes, uterus, cervix, and upper vaginal walls

if testes form, they secrete MIS, which shuts down the mullerian system

androgen insensitivity syndrome

genetic male without androgen receptors, phenotype is completely female, but no internal sex organs at all