ch. 13 Flashcards
what is the scrotum? what is the gonad it holds and what is its function
scrotum is a bag of skin holding the testes that makes sperm as well as sex androgens into the blood.
within the scrotum, where is the sperm made? what cells make it?
sperm is made within seminiferous tubules formed by the sustentacular cells.
where are male sex hormones made within the scrotum?
there is a tissue called interstitial (cells) that make the androgens
starting from the seminiferous tubules, what path does it follow to reach urethra within the penis?
seminiferous tubules to epididymis to the ductus deferens (vas deferens) that leads to the urethra
where are the seminal vesicles? what does this structure do?
they are located on the back of the bladder and secretes 60% of the semen into the ejaculatory duct
what is the duct that allows sperm into the urethra
the ejaculatory duct
where is semen created? what are these glands called together?
semen is made in the seminal vesicles, prostate, and bulbourethral glands all called the accessory glands
semen vs sperm
semen is the fluid that holds sperm cells made of fructose to protect cells and lubricate urethra
erection occurs thanks to what tissue? what occurs to make the erection
erectile tissue gets engorged with blood increasing the BP here.
what is the erectile tissue made up of
corpora cavernosa and corpus spongiosum
what are the three phase of the male sexual act? where is the control center for this activity?
the three phases are arousal, orgasm, and resolution. this is controlled by an integrating center in spinal cord that responds to physical stimuli.
what is arousal? what occurs here? what NS controls this?
arousal is dependent on PNS and divided into erection (dilation of blood vessels) and lubrication (bulbourethral glands do this)
orgasm has what two parts? what occurs here? what NS controls this?
stimulation dependent on SNS and is divided into emission: release of sperm into urethra and ejaculation: release of semen outside the body
what is resolution? which NS controls this?
resolution is the return to normal controlled by sympathetic NS and caused by constriction of erectile tissue
what is gametogenesis? what are gametes produce in males and females called?
gametogenesis is where diploid germ cells undergo meiosis to make haploid gametes. males make spermatozoa or sperm and females make ova or egg
fusion of two gametes is called? what does it produce
syngamy and it produces a zygote
sperm synthesis is called? again where does this occur with the help of what cells
spermatogenesis and occurs in seminiferous tubules with the help of sustentacular cells
where are immature sperm located in tubule? mature?
immature sperm cells are in the outer wall of the tubule while the mature gets deposited into the lumen of tubule.
what are spermatogonium? what does it do?
earliest stage of sperm and it reproduces mitotically. ITS GONium GONNA become sperm
what are primary spermatocyte?
second stage of sperm, it goes through meiosis 1 “cyte” goes through meiotic division
what are secondary spermatocyte?
third stage of sperm. it goes through meiosis 2 “cyte” goes through meiotic division
what are spermatid?
fourth stage of sperm and turns into sperm. “spermaTID is a KID”
where does sperm go to mature?
they start maturing in the seminiferous tubules and finish in the epididymis
where does sperm get its head and tail in maturation?
in the epididymis
what organelle and protein helps with sperm getting to ova? define
- acrosome: in sperm head that has hydrolytic enzymes to penetrate ovum
- bindin: exists on sperm surface to attach onto ovum
what does testosterone do for spermatogenesis?
stimulates division of spermatogonia
what does LH (luteinizing hormone) do for spermatogenesis?
stimulates interstitial cells to release testosterone
what does FSH (follicle stimulating hormone) do for spermatogenesis?
simulates sustentacular cells
what does inhibin do for spermatogenesis
it inhibits FSH so stops the production of sperm from sustentacular cells
early embryos have what ducts? which are female and which are male?
embryos have Wolffian ducts (male) and Mullerian ducts (female)
the embryonic ducts make what? without a Y chromosome, what occurs?
wolffian makes male internal genitalia and mullerian make female internal genitalia. with no y chromosome, mullerian ducts develop by default
the y chromosome starts what in the embryo
it causes the development of the testes that produce testosterone systematically and mullerian inhibiting factor
what is important to note about testosterone in embryonic process
presence of testosterone doesnt start teste formation, it just makes external male genitalia
what occurs if theres a bad testosterone receptor?
the child will not develop external male genitalia
female and male genitalia are known as what structures? gonads?
female and male genitalia are known as analogous structures while gonads are considered homologous organs
male hormones are called what? female?
male : androgens and female: estrogen
steroid sex hormones are controlled by what CNS structures
hypothalamus and pituitary gland
what is GnRH? where does it come from? what does it do
Gonadotropin-releasing hormone come from the hypothalamus to activates anterior pituitary to make LH and FSH
labioscrotal swellings become what in women? in men?
in women they become labia majora and in men, they fuse to create scrotum
what female organ releases estrogens
ovaries
in male, what becomes a penis becomes what in a women
clit
what is the path leads to the uterus from the vagina.
the vagina is a tube that goes up and ends at the cervix that then leads to the uterus
the innermost lining of the uterus is called? the smooth muscle underneath are
innermost lining is endometrium and smooth muscle is myometrium
the uterus ends in what tubes? at the end of each tube is ? what is near this structure at the end of the tube
the tubes are uterine or fallopian tubes that ends into fimbriae which are finger like structures that brush against ovaries
the female sexual act is ? where is the erectile tissue located
same as men with arousal done by PNS and orgasm by the SNS
what produces female lube
greater vestibular glands and vaginal epithelium
what is oogenesis? when does it occur
oogenesis begins prenatally where in the ovary, germ cells mitotically divide to make a large number of oogonia
what is important to note about mature oocytes
most dont get ovulated and 99% degenerate
what occurs to primary oocytes formed in fetu
they are frozen in prophase 1 for years until puberty starts and they start meiosis
oocytes go through meiosis 2?
yes they do but only when it is fertilized in womb
when oogonium go through meiosis, what is created?
three cells are made, one ova, and two polar bodies
the primary oocyte is surrounded by what structure? when it matures, what other structure is created?
is it surrounded by granulosa cells and when mature, the granulosa cells divide into layers to make zona pellucida
what are thecal cells? what hormone do they respond to
thecal are what separate follicles and respond to LH
the follicle that goes through ovulation is called
graafian follicle
what are granulosa cells called during ovulation? and after?
granulosa cells during ovulation are corona radiata and after ovulation are corpus luteum
estrogen is made by what structure in the first half of menstural cycle? and in the second half?
first half: granulosa cells
second half: corpus luteum
the menstrual cycle is how long? and what are the two cycles included?
it is avg 28 days and include ovarian cycle (primordial follicle to corpus luteum) and uterine cycle
the ovarian cycle has what 3 phases?
the follicular phase, ovulatory phase, luteal phase
FOL
what is the follicular phase:
primary follicle matures and secretes estrogen and maturation is controlled by FSH and last 13 days
what is ovulatory phase:
a secondary oocyte is released and its triggered by high LH levels. the surge causes ruminants of follicle to become corpus luteum. starts day 14
what is luteal phase:
full formation of corpus luteum and it secretes estrogen and progesterone and lasts 14 days
what is uterine cycle? what are the three phases?
uterine cycle occurs within same 28 days as ovarian cycle and gets endometrium ready for fertilization. the three phases are menstruation, proliferative phase, and secretory phase.
MPS MEGA PEEN SUPREMACY
menstruation phase:
triggered by degeneration of corpus luteum and estrogen and progesterone levels DROP. this causes lining to fall and bleeding to occur
proliferative phase:
estrogen is produced by follicle cause new endometrium
secretory phase:
occurs where estrogen and progesterone increases development of endometrium. if not baby, menstruation
what structures regulated secretion of estrogen and progesterone in the CNS
anterior pit and hypothalamus
where does LH and FSH come from
anterior pituitary
FSH causes what in women
causes granulosa and thecal cells develop in follicular phase.
LH causes what in women
causes ovulation and afterwards, it causes follicle to become corpus luteum
what occurs to hormones when pregant
High levels of P and E causes inhibition of GnRH, LH, and FSH
endometrium drops due to what
drop in P and E as corpus luteum degenerates
corpus luteum degenerates due to what hormone
LH
chorion is what? what hormone does it release
its a part of the placenta that comes from zygote and it releases HCG
what occurs in menopause
theres no P and E inhibiting LH and FSH so they stay high
during follicular phase what occur in uterine cycle?
proliferative and mensuration phases
during ovulation phase, what occurs in uterine cycle
proliferative and secretory occur
during luteal phase, what occurs in uterine cycle
secretory phase occurs
what are steps for fertilization
- sperm must penetrate corona radiata and zona pellucida using acrosome
- 2dary oocyte goes through 2 meiosis and matures
penetration of multiple sperm is called what? what prevents this?
penetration is called polyspermy. we have a fast block: depol of membrane and slow block: calcium influx
embryogenesis starts with what?
cleavage: zygote goes through many cell divisions to produce a ball of cells called morula.
morula turns into what? and this process is called
turns into blastocyte and this is called blastulation
what is the anatomy of the blastocyte
blastocytes have a ring of cells called trophoblasts and an inner cavity with an inner cell mass at the end of it
the trophoblasts turn into what? what does inner cell mass turn into?
trophoblasts turn into chorion and inner cell mass becomes embryo
where does blastocyte get nutrients from in the first 3 months? after this time, where does it get it from?
first 3 months they get it from trophoblasts
after three months: the placenta
is the corpus luteum needed during preg? why or why not?
yes it is because it makes HCG
inner cell mass also makes what structures
amnion: fluid cavity that holds embryo
yolk sac: only found in reptiles
allantois: forms blood vessels in umbilical cord
what is gastrulation?
occurs from inner cell mass where the three primary germ layers become distinct: ectoderm, mesoderm, and endoderm
after organogenesis, the embryo is now
a fetus
ectoderm
NS, pituitary, adrenal medulla, eye, skin, hair, nails (the outer layer of the organs plus NS)
mesoderm
all muscle, bone, connective tissue, cardiovascular, and urogentital, lymph
(heart and bone and muscle)
endoderm
GI tract, glands, respiratory, and bladder
(digestion and breathe)
after gastrulation what occurs
neurulation: the formation of the NS when the neural plate with the edges coming together to make neural tube
what is differentiation? what is special of primitive cells in zygote/morula
specialization of cell types. primitive cells in these structures have the potential to become any cell TOTIPOTENT CELLS
TOTIPOTENT CELLS
have potential to become any cell
what are multipotent
they can become many cells not all and they come from germ layers
when a cells fate has been fixed, it has been
determined and occur before differentiation
can cells become unspecialized?
yes this is dedifferentiation
what are pluripotent cells
can generate all adult cell types of any 3 germ layers
what occurs in first trimester?
gastrulation and neurulation
what occurs in second trimester?
organs and system continue to develop
what occurs in third trimester?
significant fat tissue
birth is called and what does it depend upon
it is also called parturition and depends on contraction of muscles in uterus. progesterone helps repress contractions during most of pregnancy
labor contraction is what kind of feedback? what hormone starts contraction
it is (+) feedback and oxytocin regulates this
prolactin is inhibited by what? what does prolactin do
it is inhibited by P and E and it causes the making of milk
oxytocin also helps with what
stimulates milk release and like before, uterine contractions
labor goes through what three things
dilation of cervix, actual birth, and expulsion of placenta
where does fertilization occur?
in the fallopian tubes
