89 terms

A&P Chapter 27 Reproductive System

male reproductive anatomy
accessory organs
primary male sex organ
location of testes
located in scrotum
function of the testes
to produce sperm and androgens
duct system for sperm delivery
ductus deferens
ejaculatory duct
accessory glands of the male reproductive system
seminal vesicles
bulbourethral glands
function of the accessory glands of the male reproductive system
secretion of semen
sac of skin hanging out side the pelvis cavity
at the root of the penis
septum separates testes
why does the scrotum keep the testes 3C lower than core body temp?
lower temp necessary for sperm production
cremaster muscle
pulls testes closer to body when they are cold
contains 500-1000 seminiferous tubules
interstitial cells surrounding tubules produce androgens
(all tubules merge and sperms enter epididymis)
seminiferous tubules
actual sperm factories
covers superior and posterior aspects of testis
cilia in epididymis cells
absorb testicular fluid
pass nurtients to sperm
sperms mature as they pass through ---
the epididymis
head, body and tail
where are sperm stored?
in the tail of the epididymis
what contracts during ejaculation?
the tail of the epididymis
expels sperm into ductus deferens
length of ductus deferens
~ 18in long
what is the largest part of the duct systems in males?
the ductus deferens
route of ductus deferens
runs from epididymis upward into pelvic cavity and loops over ureter
ejaculatory duct
formed from ductus deferens and seminal vesicles
cutting and ligating of ductus deferens
shortest portion of the duct system
ejaculatory duct
ejaculatory duct
enters prostate gland and connects to urethra
urethra in males
conveys both urine and semen
delivers sperm into female reproductive tract
includes root, shaft and glans penis
glans penis
top of penis
covered by the prepuce (fore skin)
removal of foreskin
about 60% in the US
three columns of erectile tissue
connective tissue
smooth muscle
lots of blood vessels
when erectile tissue is filled with blood
viscous alkaline fluid containing fructose, ascorbic acid and coagulating enzyme
function of semen
enhances sperm motility and fertilizing ability
provides nutrients and medium
coagulation causes sperms to stick to vaginal wall
where do sperm and semen mix?
in the ejaculatory duct
seminal vesicles
posterior to bladder
make 60% of semen volume
inferior to bladder
makes 30% of semen volume
plays role in activation of sperm
bulbourethral glands
interior to prostate
make 10% of semen volume
produce thick, clear mucus that neutralizes traces of acidic urine in urethra
female reproductive organs
accessory organs - uterine tubes, uterus and vagina
primary female organ
held in place by ligaments on either side of uterus
function of ovaries
make ova
secrete estrogen and progesterone
ovarian follicles
contained within the ovaries at various stages of development
each one contains a oocyte
a female gametocyte that develops into an ovum after two meiotic divisions
ovarian follicle stages
primordial follcile
primary follicle
secondary follicle
tertiary (vesticular) follicle
corpus luteum (yellow body)
primordial follicle stage
one layer of squamous-like cells surround oocyte
primary follicle stage
one layer of cuboidal cells surround oocyte
starts each month after puberty
secondary follicle stage
two or more layer of cuboidal cells surround oocyte
antrum formed
fluid filled inside of an oocyte from the secondary follicle stage onward
tertiary (vesicular) follicle stage
mature stage that bulges from ovary surface
ejection of oocyte from follicle
corpus luteum
yellow body
ruptured follicle that degenerates
secretes hormones
takes place as early placenta
what part of meiosis is completed only if an egg is fertilized?
meiosis II
other names of fallopian tubes
uterine tubes
fallopian tubes
receive and transport oocyte and provide site for fertilization
via fimbriae sweeping, cilia beating and peristalsis
fingerlike projections over ovary
enlarged part of fallopian tube
where fertilization usually occurs
hollow, thick-walled organ in pelvis
receives and nourishes fertilized ovum
lumen mucosal lining
undergoes cyclic changes in response to hormones
sheds during menstration
structure of the uterus
fundus - superior rounded region
body - major mid-portion
cervix - narrow neck leading to the vagina
lumen - cavity
thin-walled tube from cervix to exterior
what is embedded in the anterior wall of the vagina?
the urethra
vagina provides ---
passageway for birth, menstrual flow and copulation
muscus gladns in the vagina secrete what and why?
is metabolized by bacteria into lactic acid, which prevents a lot of bacteria and yeast from entering
low pH keeps vagina healthy
external female genitalia
mons pubis
labia majora
labia minora
mons pubis
round, fatty area overlying pubic symphysis
labia majora
elongated fatty skin folds
(homologous to male scrotum)
labia minora
skin folds within labia majora
erectile tissue hooded by skin fold
(homologous to male penis)
every cell in body other than sex cell
all have two sets from chromosomes
how many pairs of homologous chromosomes do humans have?
23 pairs of chromosomes
how many chromosomes do human sex cells have?
23 chromosomes
(haploid (n))
cell divides twice and forms 4 different cells
DNA duplication in meiosis
identical copies remain together as sister chromatids
meiosis I
homologous chromosomes split (2n to n)
synapses from triads
crossover can exchange sections of material
meiosis II
sister chromatids split
process of producing sperm via meiosis
in seminiferous tubules
happens throughout life time
what do sperm heads contain?
DNA and hydrolytic enzymes
process of producing female eggs via meiosis
starts in fetus
meiosis stalls in what stage until puberty?
prophase I
what meiosis stage is completed each month in females after puberty?
meiosis I
one of four daughter cells is ovulated and stopped in what stage?
metaphase II
follicular stage of ovarian cycle
days 1-14
follicle matures and bulges from ovary surface
ovulation stage of ovarian cycle
day 14
ovarian wall ruptures and expels oocyte
luteal phase of ovarian cycle
days 14-28
remaining follicle forms CL
CL secretes progesterone and estrogen
CL degenerates if no pregnancy
what happens with the CL if an egg is fertilized?
produces hormones until placenta is formed (at ~ three months)
menstrual cycle
uterine endometrium changes in response to hormone on monthly basis
phases of menstrual cycle
menstrual phase
proliferative pahse
secretory phase
menstrual phase of menstrual cycle
days 1-5
uterus sheds all but the deepest part of the endometrium
proliferative phase
days 6-14
endometrium rebuilds itself
secretory phase
days 15-28
endometrium prepares for embryo implantation