Transcript Chapter 28

Chapter 28
Female Reproductive Organs
• Primary female sex organs are ovaries
• Accessory sex organs are:
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Uterine (Fallopian) tubes
Uterus
Vagina
Clitoris
Mammary glands
Ovaries
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Anchored by folds of peritoneum:
1. Broad ligament – drapes over uterus
2. Ovarian ligament – suspends ovary from uterus
Ovarian Follicles
• Within cortex are thousands of ovarian follicles
– consist of an oocyte surrounded by follicle cells
• Several types of based on stages of development
Primordial Follicle
• Most primitive type
• Consists of primary oocyte surrounded by single
layer of flattened cells
Primary Follicle
• Consists of primary oocyte surrounded by 1-2 layers
of cuboidal cells
Secondary Follicle
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Contains:
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Antrum contains serous fluid
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primary oocyte
many layers of follicle cells
fluid-filled space called an antrum
increases in volume as time to ovulation nears
Two protective structures surround the primary
oocyte:
1. Zona pellucida – binds sperm
2. Corona radiata
Vesicular (Tertiary) Follicle
• Mature follicle or a Graafian
follicle
• Contains:
– secondary oocyte surrounded
by zona pellucida and corona
radiata
– enlarged antrum
– many layers of follicle cells
• When fully mature, ruptures
– ovulation
Corpus Luteum
• Following ovulation, remnants of follicle become
corpus luteum
– secretes progesterone and estrogen
• stimulates growth of uterine endometrium
Corpus Albicans
• If no implantation of embryo, corpus luteum
regresses
– turns into white connective tissue scar called corpus
albicans
Ovarian Follicles
Uterine Tubes
• Uterine tubes (fallopian tubes) extend laterally from
both sides of uterus
• Contain ciliated columnar epithelium
– Move oocyte through tube
• Secondary oocyte usually fertilized in lateral part of
uterine tube
• Takes pre-embryo ~3 days to reach the uterus
Uterine Tubes and Uterus
Uterus
• Angled anterosuperiorly across urinary bladder
– anteverted
• If positioned posterosuperiorly (projecting toward
the rectum), called retroverted
– May occur in older women
Functions of the Uterus
1. Site of implantation
2. Supports and protects the developing embryo/
fetus
3. Ejects the fetus during labor
Regions of the Uterus
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Regions of the uterus:
1. Fundus – curved superior
region between uterine
tubes
2. Body – majority of uterus
3. Cervix – narrow inferior
portion, projects into
vagina
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Cervical os - opening
Support of the Uterus
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Muscles of pelvic floor
Round ligaments – run thru inguinal ligament and
connect to labia majora
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Keep uterus anteverted
Weakness of support can result in prolapse of the
uterus
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protrudes through the vagina
Wall of the Uterus
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Uterine wall comprised of three layers:
1. Perimetrium – outermost layer of CT
2. Myometrium – thick, middle tunic comprised of
smooth muscle
3. Endometrium – mucosa composed of simple columnar
epithelium
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Two layers:
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Basal layer – permanent layer closest to myometrium
Functional layer – changes in thickness during menstrual cycle and
is shed as menses
Layers of Endometrium
Vagina
• Connects uterus to outside of body
• Opening of vagina = vaginal orifice
• Near opening, folds of mucosa form membranous barrier
called the hymen
External Genitalia
• Collectively called the vulva
External Genitalia
• Mons pubis - immediately anterior to pubic
symphysis
• Labia majora - paired, thickened folds of skin
– covered with hair
– possess sebaceous and sweat glands
– homologous to scrotum of male
• labia minora - paired folds medial to labia majora
– devoid of hair
External Genitalia
• Space between labia minora = vestibule
• Within vestibule reside the urethral opening and
the vaginal orifice
External Genitalia
• Clitoris - small (< 2 cm), erectile body located
superior to urethral opening
– homologous to penis
– Prepuce forms hood-like covering
Mammary Glands
• Produce and secrete breast milk
• Nipple - contains multiple openings
• Areola - pigmented ring of skin surrounding the
nipple
Anatomy of the Male
Reproductive System
• Primary sex organs are
testes
• Accessory organs include
glands, ducts and
tubules leading from
testes to penis
• Penis is organ of
copulation
Scrotum
• Scrotum - skin-covered sac enclosing testes
– cooler temperature
• Sperm develop at ~3 C below normal body
temperature
• Cremaster muscle – raise/lower testes for temp
regulation
Spermatic Cord
• Suspends testis from body
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Ductus (vas) deferens
Testicular artery/veins
Cremaster muscle
Autonomic nerves
• Passes thru inguinal ligament
– Superficial inguinal ring
Testes
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Two functions:
1. Production of sperm
2. Production/secretion of androgens
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primarily testosterone
Testes covered by tunica
albuginea
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Thick, fibrous capsule
Seminiferous Tubules
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Seminiferous tubules contain two types of cells:
1. Spermatogonia - population of dividing germ cells
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continuously produce sperm
2. Sertoli cells – non-dividing support cells
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assist with sperm development
Form the blood-testis barrier
beginning at puberty
Interstitial (Leydig) Cells
• In spaces in between seminiferous tubules
– Produce androgens (testosterone)
Ducts in the Male Reproductive System
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Beginning at testis and extending through penis,
ducts are:
1. Epididymis
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Stores sperm and aids in sperm maturation
2. Ductus (vas) deferens
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Carries sperm from epididymis to ejaculatory duct
3. Ejaculatory duct
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Formed by junction of ductus deferens and seminal vesicle
Located within prostate gland
Conducts sperm and seminal fluid to urethra
4. Urethra
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Transports semen (and urine) out of body
Ducts in the Male Reproductive System
Accessory Glands
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Three glands secrete fluids that mix with sperm
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seminal fluid
Secretions nourish sperm and neutralize acidity of
the vagina
1. Seminal vesicles
2. Prostate gland
3. Bulbourethral glands
Seminal Vesicles
• Paired glands located on posterior surface of
urinary bladder
– lateral to ampulla of ductus deferens
• Secrete viscous, whitish-yellow, alkaline fluid
containing fructose and prostaglandins
Prostate Gland
• Inferior to urinary bladder
• Secretes directly into
prostatic urethra
• Secretion contains:
– lubricant
– nutrients for sperm
– antibacterial protein
– prostatic-specific antigen
(PSA, enzyme that helps
liquify semen)
Bulbourethral Glands
• Located on either side of membranous urethra
• Secreted mucin for lubrication
– enters spongy urethra at base of penis
Semen
• Seminal fluid from three glands combines with
sperm to make up semen
– called ejaculate when released during intercourse
• 3-5 ml contains 200-500 million sperm
Penis
• Root - internal, attached portion of penis
• Body (shaft) - elongated portion of penis
• Glans - tip of penis
– surrounds external urethral orifice
– Glans covered by prepuce (foreskin)
Penis
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Three parallel, cylindrical
erectile bodies:
1. Paired corpora cavernosa terminate at distal shaft of
penis
2. Single corpus spongiosum •
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surrounds penile (spongy)
urethra
continues into glans
Penis