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Female Reproductive
FEMALE REPRODUCTIVE
Primary Sex Organs
• Gonads (Ovaries)
– Gametes
•Ovum or eggs
• Chromosomes• 46 Chromosomes, 23 Pairs in somatic cells
– Diploid (2N)
• 23 chromosomes in gametes
• Haploid (1N)
Secondary/Accessory Organs
• Female
– Uterine Tubes
– Uterus
– Vagina
– External genitalia
– Mammary glands
28-4
• Internal genitalia
– Ovaries, uterine
tubes, uterus, and
vagina
• External genitalia
– Clitoris, labia minora,
and labia majora
• Primary sex organs
– Ovaries
• Secondary sex organs
– Other internal and
external genitalia
The Genitalia
Figure 28.1
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Uterine tube
Urinary bladder
Ovary
Uterus
Rectum
Pubic symphysis
Fimbriae
Anterior fornix
Cervix of uterus
Anus
Posterior fornix
Prepuce
Labium minus
Labium majus
Mons pubis
Urethra
Peritoneum
Clitoris
Round ligamentVesicouterine
pouchRectouterine
pouch
Vaginal rugae
Vaginal orifice
28-5
• Internal genitalia
– Ovaries, uterine
tubes, uterus, and
vagina
• External genitalia
– Clitoris, labia minora,
and labia majora
• Primary sex organs
– Ovaries
• Secondary sex organs
– Other internal and
external genitalia
The Genitalia
Figure 28.1
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Uterine tube
Urinary bladder
Ovary
Uterus
Rectum
Pubic symphysis
Fimbriae
Anterior fornix
Cervix of uterus
Anus
Posterior fornix
Prepuce
Labium minus
Labium majus
Mons pubis
Urethra
Peritoneum
Clitoris
Round ligamentVesicouterine
pouchRectouterine
pouch
Vaginal rugae
Vaginal orifice
External Genitalia
• Collectively called the vulva
• Labium majus
• Labium minus
• Clitoris
• Mons Pubis
Vagina
• Birth Canal
• Functions
– Discharge of menstrual fluid
– Receipt of penis and semen
– Birth of baby
• Hymen
• Vaginal rugae
Ovarian arteryOvarian vein
Ovary
MesometriumFimbriae
Endometrium
Myometrium
Cervix
Uterine
tube
Suspensory
ligament
Ovarian
ligament
Vagina
Ovaries
• On each side of uterus in pelvic cavity.
• Ovarian ligaments secure them to uterus.
• Mesometrium (parietal peritoneum) holds uterus, ovary, uterine tubes in position in peritoneal cavity
• Suspensory ligaments contains ovarian artery, vein and nerves; secure ovary to pelvic wall.
Inside the ovary:
Oocyte Suspensory ligament
and blood vessels
Mature
follicleSecondary
follicle
Primary
follicles
Primordial
follicles
Ovarian
ligament
Corpus
albicansCorpus
luteum
Fimbriae
of uterine
tube
Ovulated
oocyte
•Follicles nourish the developing oocyte and secrete mostly estrogen
• Ovarian follicles > each
contain an oocyte in
different states of
maturation.
• As they mature the follicles
are called:
– Primordial follicle >
Primary follicle >
Secondary follicle>
Mature (Graafian)follicle.
PrimaryFollicle
Primaryoocyte
Secondary oocyte
SecondaryFollicle
MatureFollicle
ovulationexpelled
contains
contains
Ovarian Follicles
▪ Primordial follicle:
• a primary oocyte surrounded by a single layer of follicular cells
▪ Primary follicle:
• a larger oocytes and still single layer of follicular cells
▪ Secondary follicles
• still larger oocytes and follicular cells now stratified (granulosa cells)
▪ Mature (graafian) follicles• become fluid filled cavity
(antrum) with oocyte pushed to one side
After the ovulation:
• After the ovulation, remnants of the
follicle is called Corpus luteum > a gland
like structure.
• Corpus luteum secretes estrogen &
progesterone until it degenerates into
corpus albicans.
Uterine (Fallopian) tubes
• 2 muscular tubes - extend from ovary to uterus.
– Distal ends expand to form infundibulum.
– ampulla – middle and longest part
– isthmus – narrower end toward uterus
• Fingerlike projections called fimbriae.
Ovary
BodyFundusIsthmusAmpullaInfundibulum
Fimbriae
EndometriumInternal os
Myometrium
Lateral fornix
Cervix
Cervical canal
External os
Uterine
tube
Vagina
Uterine (Fallopian) tubes
• Walls:
– Innermost mucous - lined with ciliated cells
– middle layer - smooth muscle
• Peristalsis & ciliary action transport oocyte or fertilized
ovum to uterus
– Outer layer – serous membrane
• Site of fertilization.
• Fimbriae sweep the egg towards uterine
tube.
Uterus
Thick-walled, pear-shaped muscular chamber opening into vagina
Three anatomical segments:1. Fundus: dome shaped superior part.
2. Body: central part.
3. Cervix: narrow inferior portion joining vagina.
– Openings of cervical canal• Internal os : opening into uterus
• external os: opening into vagina
The Uterus
fundus
BodyUterine cavityInternal osCervix
External osvagina
Uterine wall:
1. Perimetrium- outer serosal layer.
2. Myometrium- middle muscular layer.
➢Labor contractions to expel the fetus
• Endometrium- innermost-highly vascular epi cells –mucosal layer
Divided into two layers:1) Stratum functionalis :
➢closer to the cavity > shed during menstruation
& rebuilt again if no implantation occurs.
2) Stratum basalis:permanent layer> build the
functional layer after each menstruation.
Vagina (birth canal)
• Extends from the cervix to the exterior.
• Common pathway for menstrual flow & the birth of a baby and receives semen
• Very distensible.
• Outer adventitia, middle muscularis & inner mucosa
• Acidic pH, but it is neutralized by slightly alkaline semen.
Mammary glands
• Nonlactating breast consists mostly of adipose and collagenous tissue
• Modified sweat glands.
• Lies over pectoral muscle, surrounded by adipose tissue.
• Each breast> pigmented projection > nipple.
• Contain milk producing glands & ducts for
delivery.
Suspensory
ligamentLobules
Lobe
Adipose tissue
Nipple
Lactiferous sinus
Lactiferous duct
RibIntercostal musclesPectoralis minorPectoralis majorFascia
Lactating breast
• 15 to 20 lobes around the nipple
• Lactiferous duct drains each lobe
• Path of milk flow: glands > lactiferous ducts > lactiferous sinus > nipple > exterior.
• Hormones of pregnancy stimulate milk production.
• Lactation: production & ejection of milk.
Adipose tissue
Suspensory
ligaments
Lobe
Lobules
Areolar glands
Areola
Nipple
Lactiferous sinus
Lactiferous ducts
Milk & Colostrum
• Colostrum:
– thin secretion before milk is produced.
– similar to breast milk but contains 1/3 less
fat,
– nutrition for first 1 to 3 days after birth
• Milk: water, proteins, fat, sugar, salts,
lysozyme, and antibody.
• Milk production- stimulated by prolactin.
• Milk ejection is controlled by oxytocin
Oogenesis
• Formation & maturation of ovum in ovary.
• Starts in fetus, but not completed until after puberty.
• Meiosis I starts before birth.
• One secondary oocyte completes maturation every month.
• After ovulation > S. oocyte enters uterine tube.
• If sperms are present, fertilization may take place.
• Ovulation: discharge of S. oocyte from ovary into pelvic cavity – every month.
Primary oocyte
Secondary oocyte + polar body
Meiosis
(2n)
(n) (n)
OOGENESIS
If sperms are present in the fallopian tube:
Sperm (n) + S. oocyte (n)
Fertilization
Zygote (2n)
Female reproductive cycles:
1. Ovarian cycle
2. Uterine/Menstrual cycle
3. Hormonal cycle
Ovarian cycle:
• Associated with maturation of egg every
month.
• Duration 28 days.
• Ovulation occurs 14th day in a 28 day
cycle.
• FSH and LH and estrogen regulates it.
• Three main events:
– Follicular phase, ovulation, luteal phase
Ovarian Cycle
Follicular Phase & Ovulation• Follicular phase from the beginning of
menstruation until ovulation
– day 1 to day 14 of an average cycle
– FSH stimulates growth of follicles and to secrete estrogen
– Menstruation - during first 3 to 5 days of cycle
• Ovulation – the rupture of the mature follicle and the release of its egg - typically around day 14
• Estrogen stimulates a surge of LH by anterior pituitary
– LH induces completion of meiosis I & production of secondary oocyte and first polar body
• Ovulation
Endoscopic View of Ovulation
© Landrum B. Shettles, MD
Fimbriae
Oocyte
Stigma
Ovary
0.1 mm
Cumulus
oophorus
Infundibulum of
uterine tube
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Ovarian Cycle
Luteal (Postovulatory) Phase• Luteal phase - days 15 to day 28
– ovulated follicle becomes the corpus luteum
– LH stimulates and maintains the corpus luteum
• If no pregnancy
– Corpus luteum eventually shrinks and becomes corpus albicans
Menstrual cycle
• Shedding & rebuilding of endometrium each month.
• Controlled by ovarian hormones.
• Closely coordinated with ovarian cycle.
• If no implantation, then 14 days after ovulation functional layer of endometrium disintegrates.
• Discharge 50-150 ml of blood, tissue fluid, cells etc.
• Caused by a fall in estrogen & progesterone
• Menstruation lasts about 5 days
Secretion
Myometrium(a) Proliferative phase (b) Secretory phase (c) Menstrual phase
Endometrial
gland
Stratum
functionalis
Stratum
basalis
Menstrual Cycle
Menstrual Cycle
28-32
Figure 28.14b
Days 1 3 5 7 9 11 13 15 17 19 21 23 25 27 1
(b) Menstrual cycle
Menstrual phase Proliferative phase Secretory phase
Th
ickn
ess o
f en
do
metr
ium
Ov
ari
an
ho
rmo
ne s
ecre
tio
n
Estradiol
Premenstrual
phase
Progesterone
Menstrual
fluid
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Hormonal cycle
• All cycles are regulated by hormones.
• Estrogen & progesterone, FSH and LH
• Released in a cyclic pattern.
• basic hierarchy of hormonal control
– hypothalamus pituitary ovaries uterus
• Starts at puberty.
Fig. 28.14
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Days 1 3 5 7 9 13 15 17 19 21 23 25 27 1
Days 1 3 5 7 9 11 13 15 17 19 21 23 25 27 1
(b) Menstrual cycle
(a) Ovarian cycle
LH
Developing follicles
PrimarySecondary
Ovulation
Luteal phaseFollicular phase
Corpus luteum Involution
Menstrual phase Proliferative phase Secretory phase
Th
ickn
ess o
f en
do
metr
ium
Ov
ari
an
ho
rmo
ne s
ecre
tio
nO
vari
an
ev
en
tsG
on
ad
otr
op
in s
ecre
tio
n
Estradiol
Progesterone
FSH
New primordial
follicles
Corpus
albicans
Tertiary
11
Premenstrual
phase
Menstrual
fluid
8-celled stage4-celled stage
Zygote
OvulationFirst polar body
Ovary
Blastocyst
Cleavage
Zona pellucida
Blastomeres
Implanted
blastocyst
(6 days)
Morula
(72 hours)
2-celled stage
(30 hours)
Corpus
luteum
Maturing
follicle
Secondary
oocyte
Second polar
body
Eggpronucleus
Spermpronucleus
Fertilization
(0 hours)
Sperm
cell
Fertilization & Implantation