Transcript Reproductive System (Genitalia)

Reproductive System (Genitalia)
Reproductive System (Genitalia)
•
•
Not vital, but essential for producing offspring
Primary sex organs:
• testis & ovary make gametes and secrete sex hormone
•
Accessory sex organs:
•
•
Male:
• Ducts: epididymis, ductus deferens, ejaculatory duct, urethra
• Glands: seminal vesicle, prostate gland, bulbourethral gl….
• Others: penis, scrotum…
Female:
• Ducts: oviduct (uterine tube), uterus, vagina
• Glands: uterine gl., bulb of vestibule, greater & lesser
vestibular gl.
• Others: clitoris, labia major & minor, mammary gl…
The Male Reproductive System
The Male Reproductive System
•
The scrotum
• skin and superficial fascia surrounding the testes
• Positioning provides an environment 3˚ C cooler than body
temperature; muscles for elevating the testes
• Dartos muscle – layer of smooth muscle
• Cremaster muscle – bands of skeletal muscle surrounding the testes
•
The spermatic cord consists of
• Ductus (vas) deferens
• Testicular a. & v. (pampiniform plexus for
countercurrent heat exchange); varicocele
• Autonomic nerve fiber.
The Testis and Seminiferous Tubules
• Are enclosed in a serous sac – the tunica vaginalis
• Tunica albuginea
• fibrous capsule of the testes divides each testis into 250•
300 lobules
Lobules contain 1-4 coiled seminiferous tubules and
epithelium consists of
• Spermatogenic cells – sperm-forming cells
• Columnar sustentacular cells – support cells (Sartoli
cells)
• Spermatogenesis – sperm formation
• Begins at puberty – 400 million sperm per day
The Scrotum – Containing the Testes and Spermatic Cord
Spermiogenesis is controlled by
ant. lobe of pituitary gl. →FSH
Leydig cell → Testosterone
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
The accessory ducts
•
•
The Epididymis:
About 6m long duct; store sperms
•
•
Dominated by pseudostratified columnar epithelium with
stereocilia (immotile, long microvilli )
• Reabsorb testicular fluid
• Transfer nutrients and secretions to sperms
20-day journey for sperm to move through
• Gain the ability to swim and to fertilize an egg (maturation)
•
The Ductus Deferens: about 45 cm; rapidly propel sperms
•
The Urethra:
• Inner mucosa; middle muscularis; outer adventitia
• Joint with duct of seminal vesicle to form ejaculatory duct
• Vasectomy for sterility
• Consists of 3 parts: prostatic, membranous and spongy
• Urethral gl. lubricates urethra
Accessory Glands (I)
• The Seminal Vesicles
• Lie on the posterior surface of the urinary bladder
• Secretes about 60% of the volume of semen contains:
• Fructose: nourish sperm with autofloresces
• Other substances to enhance fertilization
• Prostaglandins: contraction of uterus
• Suppress immune response in female
• Substances enhance sperm motility
• Clot and liquefy semen in vagina (fornix)
•
The Bulbourethral glands
• Pea-sized glands inferior to the prostate gland
• Produce mucus enters spongy urethra prior to ejaculation
• Cleanses urethra and enhances pH for fertilizations
Accessory Glands (II)
• The prostate gland
• Fibromuscular stroma encircles the prostatic urethra
• Consists of 20-30 compound tubuloalveolar glands
•
•
•
secretes about 25-30% of semen from
Contains substances that enhance sperm motility and
clot & liquefy semen
Benign prostatic hyperplasia (BPH) and prostatespecific antigen (PSA, prostatic cancer maker)
Prostate cancer
• Slow-growing – arises from peripheral glands
• Risk factors
• Fatty diet
• Genetic predisposition
Prostate Glands
BPH: benigh prostatic hyperplasia
PSA: prostate-specific antigen
Prostatitis
The Penis
Circumcision
Figure 24.8a, b
The Female Reproductive System
• Produces gametes (ova)
• oogenesis
• Prepares to support a developing embryo
• Ovulation and fertilization
• Implantation (pregnancy) and labor
• Undergoes changes according to the menstrual
cycle (28 days)
• Ovarian cycle
• Uterine cycle
Female Internal Reproductive Organs
The Uterine Ducts and Ligaments
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 24.11a
The Ovaries
• Small, almond-shaped organs
• Contain 400 million ova
• Ovarian cycle controlled by FSH and LH
(ovulation)
• Held in place by ligaments and
mesenteries
• Broad ligament
• Suspensory ligament – contains ovarian
arteries
• Ovarian ligament
The Ovarian Cycle
• Ovulation
• occurs about halfway through each ovarian cycle
• Controlled by LH
• Oocyte exits from one ovary
• Enters the peritoneal cavity, then is swept into the uterine
tube
Ectopic pregnancy
• Luteal Phase – occurs after ovulation
• Remaining follicle becomes a corpus luteum
• Secretes progesterone
• Acts to prepare for implantation of an embryo
Ovary
Oogenesis
• Includes
•
chromosomal
reduction division of
meiosis
Takes many years to
complete
The Female Reproductive System
The Uterus
Anteverted U.
Retroverted U.
Prolapse U.
Surrogate Mother
The Uterine Wall
Functional layer
Basal layer
The Uterine Cycle
•
•
•
•
Series of cyclic phases of the endometrium
Phases coordinate with the ovarian cycle
Endometrial phases directed by FSH and LH
Phases of uterine cycle
• Menstrual phase – days 1-5
• Stratum functionalis is shed
• Proliferative phase – days 6-14
• Secretory phase – days 15-28
The Menstrual Cycle
The Vagina
•
Consists of three coats
• Adventitia – fibrous connective tissue
• Muscularis – smooth muscle
• Mucosa – marked by transverse folds
• Consists of lamina propria and stratified squamous epithelium
• Cervical gland: anti-bacteria, anti-sperm
•
•
Hymen: an incomplete diaphragm
Fornix: recess formed at the superior part of the vagina
• Store semen
•
Cervical cancer – slow-growing, arises from epithelium
at the tip of the cervix
• Papanicolaou smear (Pap): cervicle smear test
The Vagina
The External Genitalia and Female Perineum
Genital triangle
Anal triangle
The Mammary Glands

Breasts – modified sweat glands
 Glandular structure – undeveloped in non-pregnant women
 Milk production – starts after childbirth
 Breast cancer – mammogram, radical mastectomy or
lumpectomy