11/22/2014 PowerPoint® Lecture Slides Reproductive System prepared by Barbara Heard, Atlantic Cape Community • Primary sex organs (gonads) - testes College and ovaries – Produce gametes (sex cells ) – sperm & ova C H A P T E R 27 – Secrete steroid sex hormones • Androgens (males) • Estrogens and progesterone (females) The • Accessory reproductive organs - ducts, Reproductive glands, and external genitalia System: Part A © Annie Leibovitz/Contact Press Images © 2013 Pearson Education, Inc. © 2013 Pearson Education, Inc. Reproductive System Male Reproductive System • Sex hormones play roles in • Testes (within scrotum) produce sperm – Development and function of reproductive • Sperm delivered to exterior through organs system of ducts – Sexual behavior and drives – Epididymis ductus deferens ejaculatory – Growth and development of many other duct urethra organs and tissues © 2013 Pearson Education, Inc. © 2013 Pearson Education, Inc. 1 11/22/2014 Male Reproductive System Figure 27.1 Reproductive organs of the male, sagittal view. • Accessory sex glands Ureter – Seminal glands Urinary bladder Peritoneum Prostatic – Prostate Seminal gland urethra (vesicle) Pubis – Bulbo-urethral glands Ampulla of Intermediate ductus deferens part of the Ejaculatory duct urethra – Empty secretions into ducts during ejaculation Rectum Urogenital Prostate diaphragm Corpus Bulbo-urethral gland cavernosum Anus Corpus Bulb of penis spongiosum Spongy Ductus (vas) deferens Epididymis urethra Testis Glans penis Scrotum Prepuce (foreskin) External urethral orifice © 2013 Pearson Education, Inc. © 2013 Pearson Education, Inc. The Scrotum The Scrotum • Sac of skin and superficial fascia • Temperature kept constant by two sets of – Hangs outside abdominopelvic cavity muscles – Contains paired testes – Dartos muscle - smooth muscle; wrinkles • 3C lower than core body temperature scrotal skin; pulls scrotum close to body • Lower temperature necessary for sperm – Cremaster muscles - bands of skeletal production muscle that elevate testes © 2013 Pearson Education, Inc. © 2013 Pearson Education, Inc. 2 11/22/2014 Figure 27.2 Relationships of the testis to the scrotum and spermatic cord. The Testes • Each surrounded by two tunics Urinary bladder – Tunica vaginalis – outer layer derived from peritoneum Superficial inguinal ring (end of inguinal canal) Testicular artery – Tunica albuginea – inner layer; fibrous Spermatic cord Ductus (vas) capsule deferens Penis Autonomic nerve fibers • Septa divide testis into ~250 lobules, each Septum of scrotum Pampiniform containing 1–4 seminiferous tubules - venous plexus Cremaster muscle Epididymis site of sperm production Tunica vaginalis External spermatic (from peritoneum) fascia Superficial fascia containing dartos Tunica albuginea Scrotum muscle of testis Skin Internal spermatic fascia © 2013 Pearson Education, Inc. © 2013 Pearson Education, Inc. Seminiferous Tubules The Testes • Interstitial endocrine cells in soft tissue • Blood supply surrounding seminiferous tubules – Testicular arteries arise from abdominal aorta • Produce androgens, e.g., testosterone – Testicular veins arise from pampiniform – Secrete it into interstitial fluid venous plexus surrounding each testicular artery • Cooler; absorb heat from testicular arteries • Keep testes cool • Spermatic cord encloses nerve fibers, blood vessels, and lymphatics that supply testes © 2013 Pearson Education, Inc. © 2013 Pearson Education, Inc. 3 11/22/2014 Figure 27.3a Structure of the testis. The Penis Spermatic cord Blood vessels and nerves • Penis consists of – Root and shaft that ends in glans penis Ductus (vas) – Prepuce, or foreskin—cuff of loose skin deferens Testis Head of epididymis covering glans Efferent ductule Seminiferous tubule – Crura Rete testis Lobule • Proximal ends of corpora cavernosa surrounded Straight tubule Septum by ischiocavernosus muscle; anchors penis to Tunica albuginea Body of epididymis pubic arch Tunica vaginalis Duct of epididymis Cavity of tunica vaginalis Tail of epididymis © 2013 Pearson Education, Inc. © 2013 Pearson Education, Inc. Circumcision The Penis: Internally • Surgical removal of foreskin • Spongy urethra and three cylindrical • 60% newborn boys in US circumcised bodies of erectile tissue (spongy network – 15% in other parts of world of connective tissue and smooth muscle – Some claim medically unnecessary with vascular spaces) – Studies show – Corpus spongiosum - surrounds urethra and expands to form glans and bulb • 60% reduction in HIV risk • Reduced risk for other reproductive system – Corpora cavernosa - paired dorsal erectile infections bodies • Erection - erectile tissue fills with blood, causing penis to enlarge and become rigid © 2013 Pearson Education, Inc. © 2013 Pearson Education, Inc. 4 11/22/2014 Figure 27.5 Male reproductive structures. The Male Duct System Ureter Urinary bladder Ampulla of ductus deferens • Ducts carry sperm from testes to body Seminal gland Prostate Prostatic urethra Ejaculatory duct exterior Orifices of prostatic ducts Bulbo-urethral gland and duct Intermediate part of the urethra – Epididymis (membranous urethra) Urogenital diaphragm Bulb of penis Root of penis Crus of penis – Ductus deferens Bulbo-urethral duct opening Ductus deferens Corpora cavernosa – Ejaculatory duct Epididymis Corpus spongiosum Body (shaft) of penis Testis – Urethra Section of (b) Spongy urethra Glans penis Prepuce (foreskin) External urethral orifice Dorsal vessels Corpora cavernosa and nerves Urethra Skin Tunica albuginea of erectile bodies Deep arteries Corpus spongiosum © 2013 Pearson Education, Inc. © 2013 Pearson Education, Inc. Epididymis Ductus Deferens and Ejaculatory Duct • Head - contains efferent ductules; superior • Ductus deferens (vas deferens) ~ 45 cm aspect of testis; body and tail on posterolateral – Passes through inguinal canal to pelvic cavity area of testis – Expands to form ampulla; joins duct of • Duct of the epididymis ~ 6 m in length seminal vesicle to form ejaculatory duct – Microvilli (stereocilia) absorb testicular fluid and pass nutrients to stored sperm • Smooth muscle in walls propels sperm • Nonmotile sperm enter, pass slowly through (~ from epididymis to urethra 20 days), become motile; can be stored several • Vasectomy - cutting and ligating ductus months deferens; nearly 100% effective form of • During ejaculation epididymis contracts, birth control expelling sperm into ductus deferens © 2013 Pearson Education, Inc. © 2013 Pearson Education, Inc. 5 11/22/2014 Urethra Figure 27.5 Male reproductive structures. Ureter Urinary bladder • Conveys both urine and semen (at Ampulla of ductus deferens Seminal gland Prostate different times) Prostatic urethra Ejaculatory duct Orifices of prostatic ducts Bulbo-urethral gland and duct Intermediate part of the urethra • Has three regions (membranous urethra) Urogenital diaphragm Bulb of penis Root of penis Crus of penis – Prostatic urethra – surrounded by prostate Bulbo-urethral duct opening Ductus deferens – Intermediate part of the urethra Corpora cavernosa Epididymis Corpus spongiosum Body (shaft) (membranous urethra) – in urogenital of penis Testis Section of (b) diaphragm Spongy urethra – Spongy urethra – runs through penis; opens Glans penis Prepuce (foreskin) at external urethral orifice External urethral orifice Dorsal vessels Corpora cavernosa and nerves Urethra Skin Tunica albuginea of erectile bodies Deep arteries Corpus spongiosum © 2013 Pearson Education, Inc. © 2013 Pearson Education, Inc. The Male Accessory Glands Accessory Glands: Seminal Glands • Paired seminal glands (seminal • On posterior bladder surface; smooth vesicles) muscle contracts during ejaculation • Paired bulbo-urethral glands • Produces viscous alkaline seminal fluid • Prostate – Fructose, citric acid, coagulating enzyme (vesiculase), and prostaglandins • Produce bulk of semen – Yellow pigment fluoresces with UV light – Remainder - sperm from testes – 70% volume of semen • Duct of seminal gland joins ductus deferens to form ejaculatory duct © 2013 Pearson Education, Inc. © 2013 Pearson Education, Inc. 6 11/22/2014 Accessory Glands: Prostate Prostate Disorders • Encircles urethra inferior to bladder; size • Prostatitis – inflammatory disorders of peach pit; smooth muscle contracts – Bacterial infection; acute and chronic; treated during ejaculation with antibiotics • Secretes milky, slightly acid fluid • Benign prostatic hyperplasia – Contains citrate, enzymes, and prostate- – May be age-related; distorts urethra; treated specific antigen (PSA) with surgery, microwaves, drugs, balloon – Role in sperm activation compression, radio-frequency radiation – Enters prostatic urethra during ejaculation • 1/3 semen volume © 2013 Pearson Education, Inc. © 2013 Pearson Education, Inc. Prostate Disorders Accessory Glands: Bulbo-Urethral Glands (Cowper's Glands) • Prostate cancer • Pea-sized glands inferior to prostate – Second most common cause of cancer death • Produce thick, clear mucus during sexual in males arousal – Digital exam screening, PSA levels – Lubricate glans penis • Biopsy if abnormal – Neutralize traces of acidic urine in urethra – Treated with surgery and sometimes radiation; castration; drugs – In clinical trials - cryosurgery, chemotherapy, ultrasound, proton beam therapy © 2013 Pearson Education, Inc. © 2013 Pearson Education, Inc. 7 11/22/2014 Figure 27.5 Male reproductive structures. Semen Ureter Urinary bladder Ampulla of ductus deferens • Milky-white mixture of sperm and Seminal gland Prostate accessory gland secretions Prostatic urethra Ejaculatory