Transcript Male reproductive system

Khaleel Alyahya
[email protected]
Monday December 7, 2009
Male Reproductive System
1. Primary reproductive organs: testes
2. Accessory reproductive structures (ducts or
glands)

duct system: epididymis, ductus deferens and
urethra.

accessory glands and semen: seminal vesicles,
prostate and bulbourethral glands.

external genitalia: scrotum and penis.
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Testes
 4 cm long , 2.5 cm wide.
 Covered with fibrous connective tissue
capsule, tunica albuginea.
The septa, extensions of tunica albuginea,
separate the testis in lobules.
 Each lobule contains 1 -4 coiled
seminiferous tubules.
 The seminiferous tubules make the
sperms.
 The seminiferous tubules are drained into
a network called rete testis.
 From rete testis the sperms go to the
epididymis
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Hormonal Control
 The pituitary controls testis function by
producing follicle-stimulating hormone
(FSH) and luteinizing hormone (LH).
 FSH stimulates spermatogenesis, in
part by affecting Sertoli cells.
 LH stimulates androgen production by
interstitial cells.
 Pituitary production of these hormones
depends on secretion of gonadotropinreleasing hormone (GnRH) by the
hypothalamus.
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Epididymis
 Comma-shaped,
coiled tube, 6 m
long
 Place for storage and maturation of
the sperms
 Passage lasts 20 days
 From the epididymis, the sperms
go to the ductus deferens
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Ducts Deferens
 Thick-walled muscular tube, which carries the sperms from the epididymis to the
ejaculatory duct (a canal inside the prostate).
 Enclosed inside a connective tissue sheath called the spermatic cord.
 Runs from the scrotum, inside the inguinal canal, into the pelvis, over the superior
surface and behind the urinary bladder
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Urethra
 Extends from the base of the urinary bladder to the tip of the penis.
 Dual function: carries urine during urination and sperm during intercourse
 Has three parts:
 prostatic urethra (inside the prostate)
 membranous urethra (from the prostate to the penis)
 spongy (penile) urethra (inside the penis)
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Seminal Vesicles
 Located at the base of the bladder.
 Their ducts join the ductus deferns to make the ejaculatory duct.
 Produce 60% of the seminal fluid.
 Their secretion provides nourishment to the sperms and activates them.
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Prostate
 Single gland the size of a chestnut.
 Located at the base of the bladder.
 Encircles the prostatic urethra.
 Its secretion activates the sperm.
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Bulbourethral Gland
 Tiny, pea-sized glands inferior to the prostate
 Produce thick mucus
 Their secretion cleanses the urethra and serves as lubricant during intercourse
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Scrotum
 A divided sac of skin hanging outside the abdominal cavity.
 Keeps the testes at optimal temperature for the spermatogenesis.
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Penis
 Cylindrical organ designed to deliver the sperm inside the female reproductive tract.
 Consists of shaft and glans covered with skin.
 The foreskin is a fold of skin covering the glans.
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Female Reproductive Organs
1. Primary reproductive organs: ovaries.
2. Duct system: uterine tubes, uterus and vagina.
3. External genitalia (vulva): mons pubis, labia,
clitoris, urethral and vaginal orifices and greater
vestibular glands.
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Ovaries
 Paired organs in the shape and size of almonds
 Contain follicles
 Each follicle contains one oocyte surrounded by layers of follicle cells
 Each mature (Graafian) follicle has an antrum (vesicular stage of maturation)
 During ovulation, the developing egg is ejected from the ovary
 After ovulation, the ruptured follicle becomes a corpus luteum
 Ovulation occurs every 28 days
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Ovulation
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Ovaries
 The ovaries are secured to the lateral walls of the pelvis by the suspensory
ligaments
 The ovarian ligaments attach the ovaries to the uterus.
 The broad ligaments are folds of peritoneum covering the ovaries
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Uterine Tube
 The uterine (fallopian) tubes receive the ovulated oocyte and provide a site for
fertilization
 Each tube is 10 cm long and extends from the ovary to the uterus
 They are enclosed in the broad ligament
 Their distal end expands in the funnel-shaped infundibulum which has finger-like
projections (fimbriae)
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Uterus
 Size and shape of a pear.
 Located in the pelvis between the urinary bladder and the rectum
 Receives, retains and nourishes the fertilized egg, accommodates the growing fetus
 Attached to the pelvis by the broad, round and uterosacral ligaments
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Uterus
 It has body, fundus and cervix
 Its wall has three layers; the inner layer (endometrium) serves as place of
implantation of the fertilized egg
 The myometrium is the middle layer of the wall
 It is made from smooth muscle and contracts during delivery
 The outermost layer of the uterus (perimetrium) is serous and is made from the
visceral peritoneum
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Vagina
 Thin-walled tube, 8-10 cm long
 Extends from the cervix of the uterus to the exterior
 Located between the bladder and the rectum
 Receives the penis and the semen during intercourse
 It is a birth canal and provides an outflow for the menses
 Its distal end isclosed by a thin fold of mucosa (hymen) which is ruptured during the
first intercourse
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External Genitalia (Vulva)
 Mons pubis is a fatty, rounded area
covering the symphysis, covered with pubic
hair
 Labia majora are two elongated haircovered folds
 Labia minora a two delicate hair-free folds
 The vestibule is an area including the
external opening of the urethra and the
vagina
 The greater vestibular glands are two
mucus-producing glands on each side of the
vagina; they provide lubrication during
intercourse
 The clitoris is a small protruding structure,
similar to the penis; it is excited during
intercourse
The perineum is a diamond-shaped region
between the mons pubis and the anus.
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Mammary Glands
 Present in both sexes, but
functional only in females.
 Produce milk to nurish a newborn
baby.
 The areola is a centrally located
pigmented area.
 The nipple is a protruding area in
the center of the areola.
 Each mammary gland has 15-25 lobes.
 Each lobule has several lobules containing alveolar glands.
 The alveolar glands produce milk.
 They are drained by the lactiferous ducts which open to the outside at the nipple.
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