reproduction Flashcards
stages of spermatogenesis
spermatogonium -> spermatogonia -> 1º spermatocyte -> 2º spermatocyte -> spermatids -> sperm
what is the precursor to male tracts called
wolffian ducts
stages of oogenesis
oögonium -> oögonia -> 1ºoocyte -> 1st polar body or 2º oocyte
what gonads develop of SrY gene is present
testes
what is the precursor to female tracts called
müllerian ducts
testicular feminization syndrome
lack of testosterone receptors, anatomically female but genetically male
genetic deficiency in conversion of testosterone to DHT
genetic male w/ testes, male reproductive tract but female external genetalia
what if adrenal glands secrete weak androgen (dehydroepiandrosterone (DHEA))
excessive amounts leads to genetic female w male bits
leydig cells
secrete testosterone
sertoli cells
support sperm development
how is sperm propelled
peristalsis
compartments of the blood-testis barrier
luminal compartment and basal compartment
functions of sertoli cells
- support sperm development
- secrete luminal fluid in which sperm develop
- secrete androgen-binding protein (androgen buffer)
- targetted by testosterone and FSH
- secrete inhibin
- secrete MIS
how is scrotum temperature regulated
dartos and cremaster muscles contract in cold
male reproductive tract
semiferous tubules -> rete testis -> efferent ductules -> epidiymus -> vas deferens
male accessory glands: seminal vesicles
secrete alkaline fluid w fructose, enzymes and prostaglandins
male accessory glands: prostate
secrete citrate and enzymes
male accessory glands: bulbourethral glands
secrete viscous fluid and mucus
Male hormone regulation: Gonadotropins
FSH - stimulates gametogenesis
Male hormone regulation: LH
stimulates androgen secretion
what part of the sperm has enzymes for fertilisation
acrosome
which NS is responsible for erection
PNS
which NS is responsible for emission and ejaculation
SNS
what receptors are in the erogenous zones of the penis
mechanoreceptors
what contracts during emission
epidedymis, vas deferens and ejaculatory tract
Granulosa cells
targetted by oestrogen and FSH, respond by secreting chemical messengers
what do granulosa cells secrete
inhibin and estrogens
functions of granulosa cells
- secrete antral fluid
- provide nutrients for developing oocyte
- secrete paracrines to support the follicle
- secrete inhibin and estrogens
- secrete substance that forms zona pellucida
what is the outer layer of the uterus called
perimetrium
what is the middle layer of the uterus called
myometrium
what is the inner layer of the uterus called
endometrium
what picks up ovum in the fallopian tubes
INFUNDBULUM and FIMBRIAE
what happens in the follicular phase of the menstrual cycle
- new follicles begin to develop from primordial follicles
- oocyte grows, granulosa cells proliferate
zona pellucida and antrum form - dominant follicle develops
- corona radiata develops
- graafin follicle (mature)
- ovulation
- FSH and estrogens stimulate growth and development
what happens in ovulation
wall of graafin follicle ruptures, antral fluid and oocyte flows to ovary surface and is released
what does the corpus luteum secrete
estrogens and progesterone
what triggers the menstrual phase
decreased estrogens and progesterone when corpus luteum degenerates
hormonal changes in the menstrual cycle
estrogen 1st secreted from follicle, then corpus luteum. progesterone secreted from corpus luteum, LH and FSH secreted from anterior pituitary, estrogens and progesterone inhibit LH and FSH secretion
what do theca cells do
increase androgen secretion
what do theca cells have receptors for
LH
actions of estrogens in the follicular phase
- promote endometrial growth
- promote oogenesis and follicle development
- increase LH receptors on granulosa cells
- increase progesterone receptors on uterus
- increase LH secretion
actions of estrogens in pregnancy
- promote growth of duct tissue in breasts
- suppress lactation
- prolactin secretion increased
- growth and contractile activity of uterine smooth muscle
- increase oxytocin receptors
- promote fluid retention
actions of progesterone in luteal phase and pregnancy
- promote secretory-phase uterine conditions
- suppress uterine contractile activity
- promotes growth of glandular tissues in breasts
- suppresses milk production
blastocyst characteristics
lost zona pellucida, has a fluid filled cavity called bastocoele
what is the outer layer of a blastocyst called
trophoblast - becomes placenta
what does the inner cell mass of a blastocyst become
embryo
how does implantation occur
trophoblast secretes enzymes that digest endometrial cells, secretes paracrines to stimulate decidual response
3 primary functions of placenta
- exchange of energy, nutrients and waste
- immunological barrier between mother and fetus
- secretes hormones that support the development of the fetus
placental hormones: Human Chorionic Gonadotropin (hCG)
maintains corpus luteum of pregnancy and stimulates secretion of testosterone
placental hormones: estrogen
stimulates growth of myometrium, increases uterine strength for parturition
placental hormones: progesterone
suppresses uterine contractions and promotes formation of cervical mucus plug
placental hormones: human chorionic somatomammotropin
reduces maternal use of glucose and promotes breakdown of stored fat
placental hormones: relaxin
softens cervix to prep for parturition
placental hormones: placental PTHrp
increases maternal plasma Ca2+ levels for calcifying fetal bones
how is ovulation prevented in pregnancy
progesterone inhibits GnRH, LH and FSH release, preventing LH surge
what is pre-eclampsia and eclampsia
increased BP in woman who are pregnant, eclampsia is large and rapid increase - life threatening
what do spasmogens do
increase force and frequency of contractions
examples of spasmogens
oxytocin and prostaglandins
what do relaxants (tocolytic agents) do + examples
reduce frequency and force of contractions - beta 2 adrenoreceptor agonists and mg ions
