A&P exam 4 Flashcards
what cells make testosterone
leydic cells= interstitial
what hormones regulate spermatogenesis
FSH and testosterone
what cations are found in ECF
Na+
what anions are found in ECF
Cl
what cations are found in ICF
K+
what anion is found in ICF
hydrogen phosphate
what is interstitial fluid composition similar to for ions
plasma
if blood osmolality increases, what happens to thirst
thirst is triggered = release ADH
what happens if osmolality decreases
inhibits thirst= no ADH release
ADH role
tells kidney to reabsorb water
where is aldosterone released from
adrenal cortex, a steroid hormone
ANP targets
hypothalamus to inhibit ADH, kidneys to release renin, adrenal cortex to inhibit aldosterone
where are osmoreceptors found
hypothalamus
where are baroreceptors found
large vessels on posterior pituitary
what does ADH cause
water reabsorption from kidneys, reduce urine volume, decrease Na+ concentration, increase ECF osmolality
what does ADH lead to
raised plasma volume and decrease ECF osmolality
ANP primary role
inhibit kidney collecting ducts, shuts off mechanism that increases BP
if BP is increased what will happen
ANP levels increase = decrease blood volume to restore BP levels
what type of urine do aldosterone and ADH form
concentrated urine
what type of urine does ANP form
large amount of dilute urine b/c less sodium and water reabsorbed
what part of the penis fills for erection
corpus cavernosum
what happens for ejaculation
contraction of ducts and glands that produce seminal fluid to cause muscle contraction
where does spermatogensis occur
seminiferous tubules
how long does spermatogenesis take
74 days
where are sperm stored
cauda epidiymis and vas deferens
steps of meosis and mitosis
what happens after meiosis 1
46 (2n) chromosomes converted to 23 chromosomes (n)
2 types of spermatogonia
Ap= lighter color, less dense
Ad= regenerate, darker, denser
Ap give rise to type B
where are Leydig cells located
near seminiferous tubules
where is FSH released from
pituitary gland
what does FSH do
causes sertolic cells to produce androgen binding protein; also increases # LH receptors causing more testosterone to be produced= maintain spermatogensis
Gonadotropin releasing hormone
hypothalamic hormone, when released goes to anterior pituitary; produces LH and FSH
phases of spermiogenic sperm production
- golgi: starts growing flagella, lots of cytoplasm
- cap: head emerges from acrosomal granule
- acrosome: nucleus becomes longer and forms distinct head cap and acrosome
- maturation: finishing differentiation to produce mature sperm
phases of spermatogenesis
proliferative: making B spermatogonia by mitosis
meiotic: begins w/ primary spermatocytes > 1st meiotic division>secondary spermatocytes > 2nd meiotic division
spermiogenic phase: spermatids undergo differentiation to make mature sperm
capacitation of sperm
in female reproductive tract, removal of decapaciting factor that allows sperm to have hyperactive motility, bind to zona pellucida, weakens acrosomal membranes
cowper’s glamd
5% semen, clear fluid, mucoproteins, lubrication
prostate gland
15-30% ejaculate, produces PSA to help activate sperm motility, Ca, Zn
seminal vesicle
45-80% semen, fructose and prostaglandins, coagulation semen
what can absence of fructose mean
vas deferens is missing/not functional
what is the primary female reproductive organ
ovary
when deos oogenesis number peak
20 weeks as a fetus= gonad has maximal oogonial content
when does body temp go up by 1 C
luteal phase
why does body temp go up by 1 C in luteal phase
higher level progesterone
when do ovaries begin producing estrogen
after puberty begins
what can increase in estrogen cause
breast development, increased skin vascularization, increase adipose tissue
what are estrogen levels controlled by
negative feedback
when does puberty in females begin
when GnRH levels increase
what hormones stimulate the ovarian cycle
LH and FSH
what happens during secretory phase of menstrual cycle
during luteal phase, endometrium develops blood vessels and glands
what phase of menstrual cycle has highest level progesterone
luteal
what stage menstrual cycle has highest body temp, lowest LH and FSH
luteal
when does estrogen peak
highest during follicular phase and is mid-level during luteal
when does progesterone peak
highest in luteal b/c made by corpus luteum= forms after ovulation
when is LH highest
luteal phase, peaks during ovulation
when are FSH levels highest
in follicular phase and peak at ovulation
after ovulation, egg is only fertilizable for how long
12-24 hours
how long can sperm live for
72 hours
what events occur during ovulation
estrogen peak before ovulation, LH and FSH peak during ovulation, prostaglandins released that facilitate oocyte release from Graafian follicle’ uterine cycle shifts to secretory phase
when do watery secretions occur from cervix
during fertile period when estrogen levels peak before ovulation
when is thick mucus secreted from cervix
infertile period, after ovulation and corpus luteum produces progesterone
why does FSH increase at end of luteal phase
FSH is repressed by high levels of progesterone and estradiol so they go down and negative inhibition of FSH is lifted
2 cell theory
- theca produce androgens when LH binds
- FSH binds to granulosa cells and convert into estrogens
what do intermediate levels of estrogen exert negative feedback on
hypothalamus, so LH and FSH aren’t released
when is there sudden positive feedback during follicular phase
levels of estradiol raise before ovulation; causes surge in LH and FSH
what declines when corpus luteum is disintegrated
thickness of endometrium
when does endometrium get thicker
during follicular phase when estrogens are high
what happens after blastocyst moves to uterus
starts dividing down the fallopian tube
what are the stages of implantation
apposition, adhesion, invasion
what happens during apposition stage of implantation
blastocyst finds spot on endometrium to eventually stick
what happens during adhesion stage of implantation
blastocyst sticks onto endometrium
what happens during invasion stage of implantation
cells from blasocyst will start moving into cell layer of endometrium
what hormone makes up the placenta
hCG, which is produced around 7 days after ovulation and goes up rapidly
what are cytorophoblasts
proliferative cells that produce S-trophoblasts
what are syncytiotrophoblasts
functional cells that make up placenta
when are syncytiotrophoblasts present
6 days after implantation and functional placenta at day 7
what maintains corpus luteum
LH
what is the #1 source of progesterone
LH
when does placenta start making hCG
after placenta can make enough progesterone and is used to maintain corpus luteum for 8-10 weeks
what do syncytiotrophoblasts do
synethsize hormones and steroids needed for pregnancy
what is needed to prevent the corpus luteum from degenerating
hCG
what are the ways of placental transport of nutrients to fetus
simple diffusion and facilitated diffusion
what does simple diffusion do
moves gases, water, electrolytes across placenta
what does facilitated diffusion do
move glucose, lactic acid using some energy
what does active transport do
move amino acids, vitamins, minerals across placenta, uses some energy
are oxygen levels the same for mom and fetus
yes, always
what nutrients preferentially goes to fetus
iron and glucose
what can cause hemorrhage of pregnancy
placenta erruption and placenta previa
what is placenta abruption
serious, painful hemorrhage that can result in loss of fetus
what is placenta previa
painless bleeding during 3rd trimester, not serious
meiosis I summary
type B divide to become primary spermatocyte. replicated chromosome seeks out partner
**chromosome # goes from 46>23
what does meiosis 2 do
converts secondary spermatoctyes (n) to spermatids (n
mitosis 1 steps
prophase, metaphase, anaphase, telophase
result of mitosis
2 diploid cells from 1 mother cell
when do chromosomes synapse and form tetrads
meiosis 1
what part of the accessory organs already contains sperm
epididymis- it is stored there and ready to be used for semen
order of accessory glands pass through
cowper’s > prostate > ampulla > epididymis > seminal vesicles
why do S-trophoblasts appear when they do
hCG increase allows them to
