The Reproductive System: Modified by Dr. Par Mohammadian 27 The Reproductive System: Modified by Dr. Par Mohammadian

Primary sex organs (gonads) - testes and ovaries Reproductive System Primary sex organs (gonads) - testes and ovaries Produce gametes (sex cells ) – sperm & ova Secrete steroid sex hormones Androgens (males) Estrogens and progesterone (females) Accessory reproductive organs - ducts, glands, and external genitalia

Sex hormones play roles in Reproductive System Sex hormones play roles in Development and function of reproductive organs Sexual behavior and drives Growth and development of many other organs and tissues © 2013 Pearson Education, Inc.

Male Reproductive System Figure 27.4A Urinary bladder (excretory system) Seminal vesicle (behind bladder) Prostate gland Bulbourethral gland Urethra Erectile tissue of penis Scrotum Vas deferens Epididymis Testis Glans of penis

Male Reproductive System Testes (within scrotum) produce sperm Sperm delivered to exterior through system of ducts Epididymis  ductus deferens  ejaculatory duct  urethra Accessory sex glands Seminal glands Prostate Bulbo-urethral glands Empty secretions into ducts during ejaculation

Figure 27.1 Reproductive organs of the male, sagittal view. Peritoneum Seminal gland (vesicle) Ampulla of ductus deferens Ejaculatory duct Rectum Prostate Bulbo-urethral gland Anus Bulb of penis Ductus (vas) deferens Epididymis Testis Scrotum Ureter Urinary bladder Prostatic urethra Pubis Intermediate part of the Urogenital diaphragm Corpus cavernosum spongiosum Spongy Glans penis Prepuce (foreskin) External urethral orifice © 2013 Pearson Education, Inc.

Sac of skin and superficial fascia The Scrotum Sac of skin and superficial fascia Hangs outside abdominopelvic cavity Contains paired testes 3C lower than core body temperature Lower temperature necessary for sperm production Temperature kept constant by two sets of muscles: Dartos muscle & Cremaster muscles

Superficial inguinal ring (end of inguinal canal) Testicular artery Figure 27.2 Relationships of the testis to the scrotum and spermatic cord. Urinary bladder Superficial inguinal ring (end of inguinal canal) Testicular artery Spermatic cord Ductus (vas) deferens Penis Autonomic nerve fibers Septum of scrotum Pampiniform venous plexus Cremaster muscle Epididymis Tunica vaginalis (from peritoneum) External spermatic fascia Superficial fascia containing dartos muscle Tunica albuginea of testis Scrotum Internal spermatic fascia Skin © 2013 Pearson Education, Inc.

Each surrounded by two tunics The Testes Each surrounded by two tunics Tunica vaginalis – outer layer derived from peritoneum Tunica albuginea – inner layer; fibrous capsule Septa divide testis into ~250 lobules, each containing 1–4 seminiferous tubules - site of sperm production; Produce androgens, e.g., testosterone Secrete it into interstitial flui

Figure 27.3a Structure of the testis. Spermatic cord Blood vessels and nerves Ductus (vas) deferens Testis Head of epididymis Seminiferous tubule Efferent ductule Rete testis Lobule Straight tubule Septum Tunica albuginea Body of epididymis Tunica vaginalis Cavity of tunica vaginalis Duct of epididymis Tail of epididymis Sperm conveyed from Seminiferous tubules Straight tubule Rete testis Efferent ductules Epididymis

Figure 27.3b Structure of the testis. Spermatic cord Ductus deferens Epididymis Testis © 2013 Pearson Education, Inc.

External genitalia - scrotum and penis Penis - male copulatory organ The Penis External genitalia - scrotum and penis Penis - male copulatory organ Penis consists of Root and shaft that ends in glans penis Prepuce, or foreskin—cuff of loose skin covering glans Circumcision: Surgical removal of foreskin 60% newborn boys in US circumcised 15% in other parts of world Some claim medically unnecessary Studies show 60% reduction in HIV risk Reduced risk for other reproductive system infections

The Penis: Internally Ureter Urinary bladder Spongy urethra and three cylindrical bodies of erectile tissue (spongy network of connective tissue and smooth muscle with vascular spaces) Corpus spongiosum - surrounds urethra and expands to form glans and bulb Corpora cavernosa - paired dorsal erectile bodies Erection - erectile tissue fills with blood, causing penis to enlarge and become rigid Ampulla of ductus deferens Seminal gland Prostate Prostatic urethra Ejaculatory duct Orifices of prostatic ducts Bulbo-urethral gland and duct Intermediate part of the urethra (membranous urethra) Urogenital diaphragm Bulb of penis Root of penis Crus of penis Bulbo-urethral duct opening Ductus deferens Corpora cavernosa Epididymis Corpus spongiosum Body (shaft) of penis Testis Section of (b) Spongy urethra Glans penis Prepuce (foreskin) External urethral orifice Dorsal vessels and nerves Corpora cavernosa Urethra Skin Tunica albuginea of erectile bodies Deep arteries Corpus spongiosum

Ducts carry sperm from testes to body exterior The Male Duct System Ducts carry sperm from testes to body exterior Epididymis Ductus deferens Ejaculatory duct Urethra Vasectomy!

The Male Accessory Glands Paired seminal glands (seminal vesicles) Paired bulbo-urethral glands Prostate Produce bulk of semen Remainder - sperm from testes © 2013 Pearson Education, Inc.

Milky-white mixture of sperm and accessory gland secretions Semen Milky-white mixture of sperm and accessory gland secretions 2–5 ml semen ejaculated, contains 20–150 million sperm/ml Contains fructose for ATP production; protects and activates sperm; facilitates sperm movement Alkaline  neutralizes acidity of male urethra and female vagina  enhanced motility © 2013 Pearson Education, Inc.

Female Reproductive Anatomy Internal genitalia – in pelvic cavity Ovaries Uterine tubes Uterus Vagina External genitalia External sex organs © 2013 Pearson Education, Inc.

Female Reproductive system Figure 27.3A Oviduct Ovaries Follicles Corpus luteum Uterus Wall of uterus Endometrium (lining of uterus) Cervix (“neck” of uterus) Vagina

Suspensory ligament of ovary Infundibulum Uterine tube Ovary Fimbriae Figure 27.12 Internal organs of the female reproductive system, midsagittal section. Suspensory ligament of ovary Infundibulum Uterine tube Ovary Fimbriae Peritoneum Uterus Uterosacral ligament Round ligament Vesicouterine pouch Perimetrium Rectouterine pouch Urinary bladder Pubic symphysis Rectum Mons pubis Posterior fornix Cervix Urethra Anterior fornix Clitoris Vagina External urethral orifice Anus Urogenital diaphragm Hymen Labium minus Greater vestibular gland Labium majus © 2013 Pearson Education, Inc.

Figure 27.14 Internal reproductive organs of a female, posterior view. Suspensory ligament of ovary Uterine (fallopian) tube Ovarian blood vessels Fundus of uterus Lumen (cavity) of uterus Uterine tube Broad ligament Ovary • Ampulla • Mesosalpinx • Isthmus • Infundibulum • Mesovarium • Fimbriae • Mesometrium Round ligament of uterus Ovarian ligament Wall of uterus • Endometrium Body of uterus • Myometrium Ureter • Perimetrium Uterine blood vessels • Internal os Isthmus • Cervical canal Uterosacral ligament • External os Cardinal (lateral cervical) ligament Lateral fornix Vagina Cervix © 2013 Pearson Education, Inc.

Uterine Wall Three layers Perimetrium - serous layer (visceral peritoneum) Myometrium - interlacing layers of smooth muscle Endometrium - mucosal lining © 2013 Pearson Education, Inc.

Uterine Vascular Supply Uterine arteries arise from internal iliacs; branch into Arcuate arteries in myometrium; branch into Radial arteries in endometrium; branch into Straight arteries  stratum basalis Spiral arteries  stratum functionalis Degenerate and regenerate; spasms  shedding of functionalis layer during menstruation © 2013 Pearson Education, Inc.

Figure 27.15b The endometrium and its blood supply. Lumen of uterus Epithelium Capillaries Uterine glands Venous sinusoids Lamina propria of connective tissue Spiral (coiled) artery Straight artery Endometrial vein Radial artery Smooth muscle fibers Arcuate artery Uterine artery © 2013 Pearson Education, Inc.