Cell bio-reproductive Flashcards
what are 3 methods of sexual differentiation?
genetic (chromosomal) sex
gonadal sex
phenotypic (somatic) sex
when is genetic differentiation determined and what are examples in mammals and in birds?
determined at fertilization
XX, XY mammals
ZZ (male) ZW (female) birds
how is gonadal sex differentiation determined?
testis determining genes (SRY & SOX9)
What are 2 structures involved in phenotypic sex differentiation and what are 3 hormones involved?
tubular & external structures
antiMullerian hormone, tesosterone, Dihydrotesterone
define hormones
signaling molecules produced in the body that regulate activity of certain cells and organs
what are 6 examples of body functions regulated by hormones?
metabolism sleep lactation growth mood reproduction
how are hormones secreted and what is an example?
by specific glands
thyroid
what are 3 main classes of hormones?
steroids
peptides/proteins (glycoproteins)
eicosanoids
how do hormones induce response?
bind to specific receptors
how is hormone control regulated? (2)
negative or positive feedback
what are two methods used to classify hormones?
production
biochemical structure
What are 5 sources of production used in hormonal classification?
hypothalamic hormones pituitary hormones gonadal hormones uterine hormones hormones of placenta
what is the structure of peptides and what is an example?
small molecules with few AA
GnRH
What is the role of GnRH and what are 2 hormones what are secreted in this way?
regulates pituitary gonadotropin secretion
LH & FSH are secreted from the same gonadotrope cell after GnRH stimulation
What is the structure of glycoproteins and what are 3 examples?
alpha subunit & beta subunit bound by H bonds and vander Waals forces with CHO bound on each end by covalent bonds
FSH, LH, TSH
what are important facts of the alpha and beta subunits of glycoproteins?
alpha subunits are common among hormones
beta subunits are unique for each hormone
what is the structure of steroids?
3 hexa rings, 1 penta ring and a side chain
what is the structure of prostaglandins and what are 2 types?
penta ring with O or OH bound, a chain with 2 double bonds and a COOH at the end
PGF2alpha
PGE2
what are 3 domains of a receptor?
extracellular
transmembrane
intracellular
what type of receptors do protein hormones bind to?
cell-surface receptor
what type of receptors do steroids bind to?
nuclear receptors
what are progesterone, estradiol & testosterone synthesized from?
cholesterol
where is Esteradiol-17beta mainly produced, where is it also produced and what are 3 other sites what can produce smaller amounts?
how is it synthesized and where is it metabolized?
mainly follicular cells in ovary placenta smaller adrenal, testis, fat two-cell, two gonadotrophin synthesis metabolized in liver
what are 8 functions of estradiol?
mediate sexual behavior & 2nd characteristics of female uterine development & function cervical mucus vaginal proliferation mammary development (ductal) maintaining pregnancy bone health
where is progesterone produced, and when is the structure formed?
mainly by ovary
specifically corpus luteum
formed after ovulation
progesterone is the proliferation & differentiation of what two cells, what do they produce and where is it metabolized?
granulosa cells (large luteal cells) & theca interna cells (small luteal cells)
produce progesterone
liver
what are 6 functions of progesterone?
development & function of uterus myometrium maintenance of pregnancy development of mammary gland (alveoli) effects on brain effect son immune function
what cells produce testosterone and where, what are 2 locations that produce small amounts, what is the main site of metabolism and what is a seond site?
interstitial (leydig) cells of testis
smalled amounts in adrenal and ovaries
metabolized by liver
lesser in prostate
what are 5 functions of testosterone?
masculinization maturation & function of male reproductive tract spermatogenesis male sexual behavior muscle mass, bone density
what are 2 functional areas for secretion of GnRH in the female hypothalamus?
tonic center (arcuate ventromedial region- ERC) surge center (preoptic area- POA)
what is the effect of testosterone on the brain?
“defeminizes” the brain
crosses BBB and converts to estradiol, which defeminizes hypothalamus, eliminating surge center
what is the difference for fetal ovaries and their effect on the hypothalamus?
the estradiol produced does not cross the BBB because it is bound to alpha-fetoprotein
define estrous cycle
period form beginning of one estrus to the beginning of the next
(one ovulation to the next)
what are 3 phases of the estrous cycle and what is another name for each phase in women?
follicular phase (proliferative phase in women) luteal phase (secretory phase in women) Quiesten phase (anestrus)
how is estrus defines?
behaviorally
