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Explore male and female reproductive systems. Learn about testes, ovaries, sperm production, egg development, and hormonal control. Understand the intricacies of genitalia functions and essential processes for reproductive health.
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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 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
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 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
The Uterine Ducts and Ligaments 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
Oogenesis • Includes chromosomal reduction division of meiosis • Takes many years to complete
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 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 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