Reproductive System (Genitalia)

1. Reproductive System (Genitalia)

2. 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…

3. The Male Reproductive System

4. 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.

5. 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

6. The Scrotum – Containing the Testes and Spermatic Cord

7. Spermiogenesis is controlled by ant. lobe of pituitary gl. →FSH Leydig cell →Testosterone

8. 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

9. 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

10. 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

11. Prostate Glands BPH: benigh prostatic hyperplasia PSA: prostate-specific antigen Prostatitis

12. The Penis Circumcision Figure 24.8a, b

13. 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

14. Female Internal Reproductive Organs

15. The Uterine Ducts and Ligaments Figure 24.11a

16. 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

17. 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

18. Ovary

19. Oogenesis • Includes chromosomal reduction division of meiosis • Takes many years to complete

20. The Female Reproductive System

21. The Uterus Anteverted U. Retroverted U. Prolapse U. Surrogate Mother

22. The Uterine Wall Functional layer Basal layer

23. 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

24. The Menstrual Cycle

25. 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

26. The Vagina

28. The External Genitalia and Female Perineum Genital triangle Anal triangle

29. 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