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

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Spermiogenesis is controlled by ant. lobe of pituitary gl.

→FSH Leydig cell → Testosterone

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• Inner mucosa; middle muscularis; outer adventitia• Joint with duct of seminal vesicle to form ejaculatory duct• Vasectomy for sterility

• The Urethra:• 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 prostate-

specific 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

Figure 24.8a, b

Circumcision

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

tubeEctopic 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

Anal triangle

Genital 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