chp 27 pp Flashcards
Reproductive organs are grouped by
function gonads ducts accessory sex glands supporting structures
gonads
testes and ovaries
- produce gametes and secrete hormones
- produce gametes and fluid; then discharge into duct system indicates exocrine function
- production of hormones indicates endocrine function
receive, store, transport gametes
Ducts
produce gametes and secrete hormones
gonads
support gametes
Accessory sex glands
supporting structures
various reproductive functions
a system of ducts, accessory sex glands, and several supporting structures
testes
2 fibrous sacs which support and protect the testes
scrotum
muscles of the scrotum
cremaster muscle
dartos muscle
sperm production requires temp
3 C below body temp
involuntary muscle contraction does what to the testes
raises them
paired oval glands 5 cm x 2.5 cm
testes
development influenced by Y sex chromosome and by maternal hormonal levels
testes
where do the testes develop
in the abdomen
what are the testes surrounded by
dense connective tissue
also forms septa creating lobules
200-300 lobules/testicle
internal fibrous capsule = tunica albuginea
internal fibrous capsule of the testes
= tunica albuginea
what cover the testes
tunica vaginalis (serous membrane) from peritoneum
how many seminiferous tubules in each lobule
3
Each seminiferous tubule is lined with
spermatogenic cells in various developmental stages
prevents immune system response to sperm antigens in the testes
Blood-Testis Barrier
Sustentacular (Sertoli) cells
- create blood-testis barrier with tight junctions
- respond to FSH and testosterone
- phagocytize shed excess spermatid cytoplasm
- control sperm movement and release into the tubule lumen
- secrete some nutrients for sperm
- secrete some fluid for sperm transport
Interstitial endocrinocytes (interstitial cells of Leydig) are located
between tubules
Interstitial endocrinocytes (interstitial cells of Leydig) secrete
testosterone in response to LH (= ICTH)
Spermatogonia undergo what to give rise to spermatazoa
meiosis
during spermatogenesis where does meiosis occur
occurs in the seminiferous tubules
what do spermatogenesis produce
haploid spermatozoa
how long do sperm live
64-72 days in humans
what are spermatogonia
diploid stem cells
by what mechanism do some spermatogonia remain as viable stem cells throughout their life
mitosis
if spermatogonia don’t remain as viable stem cells what can occur
others undergo developmental changes to become primary spermatocytes and undergo meiosis
Reduction division
divided into three stages
1) primary spermatocytes undergo meiosis I to become secondary spermatocytes (haploid)
2) secondary spermatocytes undergo meiosis II to become immature spermatids (haploid)
3) Spermatids mature morphologically into spermatozoa = sperm cells
primary spermatocytes undergo
meiosis I to become secondary spermatocytes (haploid)
secondary spermatocytes undergo
meiosis II to become immature spermatids (haploid)
Spermatids mature morphologically into
spermatozoa = sperm cells
what happens with spermatids cytoplasm
do not separate their cytoplasm completely
they maintain cytoplasmic bridges until released into the tubule lumen
what do spermatids mature to
spermatozoa
what is spermatogenesis
spermatids maturing to spermatoza
How long does Spermatogenesis
take
Requires 10-14 days for migration to and 3-4 days for maturation in the ductus epididymus
how are older sperm removed
gradually by phagocytes within the epididymus
are sperm normal or abnormal
Many sperms are abnormal, either morpholically, physiologically, or genetically
30% abnormal is considered “normal”
sperm cells are called
Spermatozoa
how many Spermatozoa mature a day
300 million/
how long do spermatoza survive following ejaculation
about 48 hrs following ejaculation in the female reproductive tract
what is it called when testosterone & DHT stimulate enlargement of male sex organs and secondary sexual characteristics
Puberty
what stimulates pattern development before birth (internal ducts)
testosterone
what pathway do sperm move through the ducts
move slowly from the lumen of seminiferous tubules straight tubules rete testis epididymis
what help move sperm along through ducts
continuous sperm and testicular fluid production move sperms along
what does the fluid in the ducts contain
H2O, androgens, estrogens, K+, glutamic acid, aspartic acid
posterior border of testes
epididymis
is tightly coiled tube - head, body, tail
6 m long if uncoiled
epididymis is made up of what tissue
pseudostratified columnar epithelium
- microvilli provide nutrients
- reabsorb testicular fluid
- phagocytize degenerating older sperm
ductus epididymis
is
site of sperm maturation (10-14 days) - motility
may remain in storage for a month, then reabsorbed
Ductus (vas) deferens
- less convoluted with a larger diameter
- ascends, enters pelvic cavity through inguinal canal
- loops up, over urinary bladder to end in the ampulla
Ductus (vas) deferens
- pseudostratified columnar epithelium with thick muscularis
- transports sperm from epididymis to urethra by peristalsis during ejaculation
Ejaculatory Ducts are formed by
ducts from seminal vesicle and ductus deferens
Ejaculatory Ducts move
sperm into prostatic urethra before ejaculation
in males terminal tract for urinary and reproductive systems
urethra
what are the three regions of the males urethra
- prostatic urethra
- membranous urethra
- spongy (cavernous) urethra
where does the urethra end on a male
at external urethral orifice at the bulb/glans of the penis
Accessory sex glands on males
seminal vesicles, prostate, and bulbourethral glands
Accessory sex glands secrete what
the fluid portion of the semen
Seminal vesicles
- base of urinary bladder
- 60% of semen volume
the male accessory sex glands secrete alkaline viscous fluid containing:
- fructose, ascorbic acid
- prostaglandins
- vesiculase (coagulating enzyme) keeps semen near cervix while sperm swim into cervix via flagellar movements
below bladder, around urethra in males
prostate
what does the prostate secrete in males
secretes milky, slightly acidic fluid with: citrate enzymes phosphatase fibrinolysin prostate specific antigen (PSA)
Bulbourethral (Cowper’s) glands in males
-beneath prostate gland at membranous urethra
-secrete:
alkaline fluid
mucus
-neutralize acidic urine
mixture of sperms and secretions
Semen
is sperm more acidic or alkaline
milky and mucoid
and alkaline to decrease acidity of vagina
seminalplasmin
is a
natural antibiotic
what happens to semen after ejaculation into vagina
coagulates
penis is made up of
root (attachment)
body (shaft)
glans penis (head)
root of penis is also called
bulb
3 cylindrical tissue masses surrounded by tunica albuginea
body of the penis
Each section of the penis body has
blood sinuses = erectile tissue
Arteries dilate with sexual stimulation, a parasympathetic reflex causes
an erection
what causes an erection in a male
Large quantities of blood enter the sinuses
- compress superficial veins from sinuses
- trapped blood erection
what happens to a bladder sphincter during erection in a male
Close bladder sphincter
- prevent urine flow
- prevent semen backflow
what type of reflex is ejaculation
sympathetic
Paired, small (pecan-sized) oval organs in the pelvic cavity
ovaries
what are the ovaries supported by
several complex fibrous ligaments
what kind epithelium are ovaries
Germinal epithelium
what is the connective tissue in the ovary
Tunica albuginea
fibrous connective tissue
in ovaries
stroma
outer dense layer with ovarian follicles containing eggs = oocytes
cortex
inner loose fibrous connective tissue layer containing blood vessels
medulla
ovarian follicles consist of
- Primary follicles
- Secondary follicles with antrum formation
- Vesicular (Graafian)
follicles with large antrums
-Vesicular (Graafian)
follicles with antrum formation
Secondary follicles
after ovulation what form
Corpus luteum (“yellow body”) Corpus albicans (“white body”)
Formation of haploid ova in the ovary
Oogenesis
steps of female reproduction
1) Reduction division - meiosis I (haploid)
2) Equatorial division - meiosis II
3) Maturation – potential for fertilization
structure of uterine
(1) infundibulum with fimbriae
(2) ampulla
(3) isthmus
Extend laterally from uterus to transport ova by peristalsis and cilia-generated current from the ovaries to the uterus
uterine (Fallopian) tubes = oviducts
Uterine tube histology- 3 cell layers
1) internal mucosa - ciliated columnar epithelial cells and secretory cells
2) middle muscularis
inner thick circular layer of smooth muscle
outer thin longitudinal layer of smooth muscle
peristaltic contractions and cilia-generated current move secondary oocyte toward uterus
3) outer serous membrane - perimetrium
what happens once a month for females
Once a month an ovarian follicle ruptures releasing a secondary oocyte (ovulation)
Oocyte drawn into the oviduct
by cilia-generated current on the fimbriae and within the tube by cilia and peristalsis
where does fertilization occur
- ideally in the ampulla – upper third of oviduct
- becomes a zygote and then begins mitotic divisions
what happens to unfertilized oocytes
disintegrate and are swept out
Site of menstruation, implantation, fetal development, labor
uterus
Size and shape of an inverted pear
uterus
3 parts of Uterus
1) Fundus
2) Body with
3) Isthmus
narrow portion that opens into vagina
cervix
what does the cervix produce
produces cervical mucus; (20-60 mL/day)
what does the mucus plug do
keep microbes out
what does cervix, mucus do
- protect spermatazoa
- provide nutrients
- role in capacitation
Uterus bends
between its body and cervix
Uterus joins with
the vagina at a right angle
what do ligaments provide for females
provide stability – important especially during labor
ligaments
- broad ligaments
- uterosacral ligaments
- cardinal ligaments
- round ligaments
3 uterine layers
perimetrium
myometrium
endometrium
myometrium
-3 layers of smooth muscle
-thickest in fundus
-thinnest in cervix
for expulsion at labor
Perimetrium
= visceral peritoneum
endometrium
- highly vascular
- surface layer
- simple columnar epithelium
- ciliated, secretory cells
- uterine (endometrial) glands
3 layers of the endometrium
1) stroma (lamina propria) of glandular and connective tissues
- divided into 2 layers:
2) stratum functionalis (functional layer) shed during menstruation
3) stratum basalis (basal layer) - gives rise to stratum functionalis
female reproductive system gets its blood supply
from uterine arteries
- arcuate arteries
- radial arteries
circular arteries around the myometrium
arcuate arteries
radial arteries penetrate
into the myometrium with smaller branches
what arterioles change during menstruation
spiral arterioles
labor and delivery is called
fetal expulsion
what help regulate labor
Oxytocin and prostaglandins
what does ANS do
control contractions
Tubular, fibromuscular organ with mucous membrane
vagina
Between bladder, rectum
vagina
vagina has several functions
passage for menstrual flow, childbirth
receives penis and semen
what is the vaginal oriface called
hymen
areolar connective tissue
Adventitia
stretches to receive penis and for accommodating childbirth
Muscularis
muscularis is made up of
smooth muscle - outer circular, inner longitudinal layers
- pudendum
- Female external genitalia
vulva
anterior, adipose tissue
mons pubis
- lateral skin folds with sebaceous and sudoriferous glands
- homologous to scrotum
labia majora
medial folds with sebaceous glands
labia minora
clitoris
- Anterior junction of labia majora
- Small cylindrical mass of erectile tissue and nerves
- Plays a role in sexual excitement
- Homologous to penis; has prepuce and glans
Vestibule
- Region between labia minora
- Mostly the vaginal orifice
- Bulb of vestibule
Bulb of vestibule
- 2 elongated masses of tissue
- fill with blood during sexual arousal
- narrows vaginal orifice
- increases pressure on penis
- homologous to corpora spongiosum and bulb of penis
External urethral orifice
- Anterior to vaginal orifice, posterior to clitoris
- Exterior opening of the urinary tract
- Proximity to vagina and anus increase risk of UTI
accessory glands on the female reproductive system
- Paraurethral (Skene’s) glands
- Greater vestibular (Bartholin’s) glands
Paraurethral (Skene’s) glands
- On either side of external urethral orifice in the vulva
- Secrete mucus
- Homologous to prostate gland
Greater vestibular (Bartholin’s) glands
- Open in the area between hymen and labia minora
- Mucus secretion during sexual intercourse
- Some lesser vestibular mucous glands also present
- Homologous to bulbourethral (Cowper’s) gland
- Diamond shaped area between thighs, buttocks
- Contains external genitals, anus
- anterior - pubic symphysis
- posterior - coccyx
perineum
Episiotomy
to ease labor
mammary glands
Modified sudoriferous (sweat) glands that produce milk
- exterior pigmented projection
- many closely spaced openings - lactiferous ducts
nipple
- surrounding pigmented area
- sebaceous (oil) glands
Areola
mammary glands have how many lobes
15-120
Mammary Gland Development
- Develop at puberty due to estrogen, progesterone
- Ducts develop, fat deposition occurs
- Areola and nipple enlarge; become pigmented
- Further development occurs following ovulation and corpus luteum formation in menstrual cycle or pregnancy
mammary glands Primary function is
milk synthesis
Secretion and ejection together =
lactation
Primary stimulus for milk production is
prolactin from the anterior pituitary
Stimuli for milk release (letdown) in response
suckling:
- oxytocin from posterior pituitary
- ANS reflexes
how many women will have breast cancer
12%
3.5% will die of breast cancer
risk factors for breast cancer
- family history
- early onset menses and late menopause
- no child or first child after age 34
- previous breast cancer
- exposure to ionizing radiation (x-rays)
- obesity, alcohol intake, cigarette smoking
Treatment
for breast cancer
- lumpectomy (removal of tumor and surrounding tissue)
- radical mastectomy (breast, pectoral muscles, axillary lymph nodes)
Ovarian hormones target
uterus and breast
Anterior Pituitary hormones target
ovary
Hormones target several organs in the female reproductive system
Ovaries – Uterus – Breasts – CNS
3 Phases of Reproductive cycle
1) Day 1-4 - menstrual phase
2) Day 5-14 - preovulatory (proliferative) phase
3) Day 15-28 - postovulatory (secretory) phase
levels of estrogen/progesterone go down is
negative feedback
uterine spiral arteries constrict and
creates ischemic tissue
FSH levels rise (from day 25 of cycle) to
stimulate a few primordial follicles to develop into primary follicles
All follicles release low levels of
estrogen
by day four 20 follicles in the ovary
develop into primary and then secondary (growing) follicles
Preovulatory Phase - lasts
6-13 days
Menstrual and Preovulatory phase together are known as the
Follicular phase
By day 6 of the cycle, one follicle
outgrows others
dominant follicle does what
secretes & inhibin
estrogen & inhibin do what
reduce FSH secretion and all other follicles stop growing and degenerate = atresia
atresia
all other follicles stop growing and degenerate
what happens to estrogen when one follicle outgrows the other
estrogen levels increase
dominant follicle matures and is called, forming
- vesicular ovarian (Graafian) follicle (mature follicle)
- forms a blister-like bulge on the surface of the ovary
Preovulatory Phase
1) Menstrual and Preovulatory phase together are known as the Follicular phase
2) By day 6 of the cycle, one follicle outgrows others
3) Dominant follicle matures
4) Follicle continues to secrete estrogen
5) Estrogen stimulates endometrial regrowth
Follicle continues to secrete estrogen
FSH is dominant early
Close to ovulation, LH becomes important
Estrogen stimulates endometrial regrowth
- stratum basalis
- mitosis creates a new stratum functionalis
- endometrial glands redevelop
- arterioles coil and lengthen
what causes a rupture of vesicular follicle
LH pulse causes rupture of vesicular = Graafian follicle and release of oocyte into the pelvic cavity; occurs approximately day 14
when fimbriae becomes more active
cilia create currents in peritoneal fluid to carry oocyte into uterine tube
Secondary oocyte
- surrounded by follicular cells, corona radiata
- secondary oocyte in metaphase II
what happens when estrogen causes changes in body temp
cervical mucus becomes less gelatinous
Prior to ovulation
- high estrogen exerts positive feedback on FSH, LH
- sudden surge of LH causes release of oocyte
- LH surge is measurable
Following ovulation
1) follicle collapses becoming corpus hemorrhagicum
2) follicular cells then enlarge, change character, form the corpus luteum
3) follicular cells respond to LH by secreting estrogen and now progesterone
Postovulatory Phase
- Most constant in duration, lasts for 14 days, from ovulation to the next menses
- LH stimulates corpus luteum development (luteal phase); corpus luteum secretes increased levels of estrogen and progesterone
- Progesterone prepares endometrium to receive an embryo (if it has developed sufficiently)
Progesterone prepares endometrium to receive an embryo (if it has developed sufficiently)
- growth and coiling of endometrial glands
- vascularization of surface endometrium
- endometrial thickening
- increased tissue fluid
- secretory phase for the endometrial glands
Postovulatory Phase
If no fertilization
- estrogen and progesterone rise inhibit GnRH and LH
- corpus luteum degenerates (no LH) corpus albicans
- Levels of estrogen and progesterone DROP
What happens during the postovulatory phase when levels of estrogen and progesterone drop
- stop endometrial development
- stimulate next menstruation
- stimulate anterior pituitary hormones to begin next cycle
If fertilization occurs
- corpus luteum maintained until the placenta takes over
- maintained by hCG (human chorionic gonadotropin)
- placenta produces estrogen, progesterone
home pregnancy test detects
hCG
stimulation causes vasodilation of capillary sinuses, compression of veins erection
parasympathetic
define male orgasm
sensory input including HR, BP, RR, pleasurable sensations, along with ejaculation
Female Reproductive Act
Arousal – mediated by
Parasympathetic Division of ANS
stimulation of breasts, genitalia, especially the clitoris, generat
Orgasm (climax) - maximal tactile stimulation of genitalia results in orgasm, mediated by
Sympathetic Division (ANS)
Sterilization
vasectomy in males and tubal ligation in females (tubes cut and sealed)
Oral contraception – simulate “pregnant state”
- generally higher in progesterone and lower in estrogen
- negative feedback inhibition of FSH, LH and GnRH
- prevents follicular development and ovulation
- also alter cervical mucous and make endometrium less receptive to implantation
The only method likely to prevent STD’s and reliable when used correctly
condoms
