Reproductive

• Gonads


  Testes in males; ovaries in females
• Ducts


  Store and transport the gametes
• Accessory male genital glands


  Produce substances that protect the gametes and facilitate their movement
• Andrology


  The branch of medicine that deals with male disorders, especially infertility and sexual dysfunction
• Functions of the Male Genital System

  • The testes produce sperm and the male sex hormone testosterone
  • The ducts transport, store, and assist in maturation of sperm
  • The accessory male genital glands secrete most of the liquid portion of semen
  • The penis contains the urethra, a passageway for ejaculation of semen and excretion of urine
• Scrotum


  The supporting structure for the testes, consists of loose skin and underlying subcutaneous tissue that hangs from the root (attached portion) of the penis
• Scrotum


  • Raphe - Externally, the scrotum looks like a single pouch of skin separated into lateral portions by a median ridge
  • Scrotal septum - divides the scrotum into two compartments, each containing a single testis
  • Dartos muscle - The septum is made up of a subcutaneous tissue and muscle tissue
  • Cremaster muscle - a series of small bands of skeletal muscle that descend as an extension of the internal abdominal oblique muscle through the spermatic cord to surround the testes
• Testes


  Paired oval glands in the scrotum measuring about 5 cm (2 in.) long and 2.5 cm (1 in.) in diameter. Each testis (singular) has a mass of 10–15 grams. The testes develop near the kidneys, in the posterior portion of the abdomen, and they usually begin their descent into the scrotum through the inguinal canals (passageways in the lower anterior abdominal wall) during the latter half of the seventh month of fetal development
• Testes


  • Tunica vaginalis - which is derived from the peritoneum and forms during the descent of the testes, partially covers the testes
  • Hydrocele - accumulation of serous fluid in the tunica vaginalis
  • Tunica albuginea - white fibrous capsule composed of dense irregular connective tissue
  • Lobules - septa that divide the testis into a series of internal components
  • Seminiferous tubules - where sperm is produced
  • Spermatogenesis - the process by which the seminiferous tubules of the testes produce sperm
  • Spermatogonia - stem cells that develop from primordial germ cells
  • Nurse cells - also called sustentacular cells or Sertoli cells, which extend from the basement membrane to the lumen of the tubule
  • Blood-testis barrier - Internal to the basement membrane and spermatogonia, tight junctions join neighboring nurse cells to one another. These junctions form an obstruction known as the blood–testis barrier because substances must first pass through the nurse cells before they can reach the developing sperm
  • Interstitial endocrine cells - or Leydig cells, clusters of cells in the spaces between adjacent seminiferous tubules
  • Androgen - hormone that promotes the development of masculine characteristics
• Ducts of the Testis

  1. Straight tubules - Pressure generated by the fluid secreted by nurse cells pushes sperm and fluid along the lumen of seminiferous tubules and then into a series of very short ducts

  2. Rete testis - straight tubules that lead to a system of ducts in the testis

  3. Efferent ductules - From the rete testis, sperm move into a series of coiled efferent ductules in the epididymis that empty into a single tube called the duct of epididymis
• Epididymis


  An organ about 4 cm (1.5 in.) long that curves along the superior and posterior border of each testis, having a comma shape in profile
• Epididymis

  • Duct of epididymis - each epididymis consists mostly of the tightly coiled
  • Head of epididymis - The efferent ductules from the testis join the duct of epididymis at the larger, superior portion of the epididymis
  • The body of epididymis - is the narrow midportion of the epididymis, and the tail is the smaller, inferior portion. At its distal end, the tail of the epididymis continues as the ductus deferens
  • Stereocilia - which despite their name are long, branching microvilli (not cilia) that increase the surface area for the reabsorption of degenerated sperm
  • Sperm maturation - the process by which sperm acquire motility and the ability to fertilize an ovum. This occurs over a period of about 14 days
• Ductus Deferens


  Or vas deferens, The ductus deferens, which is about 45 cm (18 in.) long, ascends along the posterior border of the epididymis through the spermatic cord and then enters the pelvic cavity. There it loops over the ureter and passes over the side and down the posterior surface of the urinary bladder
• Ductus Deferens

  • The ductus deferens conveys sperm during sexual arousal from the epididymis toward the urethra by peristaltic contractions of its muscular layer. Like the epididymis, the ductus deferens also can store sperm for several months. Any stored sperm that are not ejaculated by that time are eventually reabsorbed
  • Ampulla - dilated terminal portion of ductus deferens
• Spermatic cord


  A supporting structure of the male genital system that ascends out of the scrotum
• Spermatic cord


  • Inguinal Canal - an oblique passageway in the anterior abdominal wall just superior and parallel to the medial half of the inguinal ligament. The canal, which is about 4–5 cm (about 2 in.) long, originates at the deep (abdominal) inguinal ring, a slitlike opening in the aponeurosis of the transversus abdominis muscle; the canal ends at the superficial (subcutaneous) inguinal ring
  • Varicocele - refers to a swelling in the scrotum due to a dilation of the veins that drain the testes. It is usually more apparent when the person is standing and typically does not require treatment
• Ejaculatory Ducts


  About 2 cm (1 in.) long and is formed by the union of the duct from the seminal gland and the ampulla of the ductus deferens. The short ejaculatory ducts form just superior to the base (superior portion) of the prostate and pass inferiorly and anteriorly through the prostate. They terminate in the prostatic urethra, where they eject sperm and seminal gland secretions just before the release of semen from the urethra to the exterior
• Urethra


  The shared terminal duct of the genital and urinary systems; it serves as a passageway for both semen and urine
• Urethra


  • Prostatic Urethra - is 2–3 cm (1 in.) long and passes through the prostate
  • Membranous urethra - deep muscles of perineum
  • Spongy urethra - corpus spongiosum of the penis
  • External urethral orifice - where the spongy urethra ends
• Seminal Glands

  Or seminal vesicles, are convoluted pouchlike structures, about 5 cm (2 in.) in length, lying posterior to the base of the urinary bladder and anterior to the rectum
• Seminal Glands


  • Seminal fluid - an alkaline, viscous fluid that contains fructose (a monosaccharide sugar), prostaglandins, and clotting proteins that are different from those in blood
• Prostate


  A single, doughnut-shaped gland about the size of a golf ball. It measures about 4 cm (1.6 in.) from side to side, about 3 cm (1.2 in.) from top to bottom, and about 2 cm (0.8 in.) from front to back. It is inferior to the urinary bladder and surrounds the prostatic urethra
• Prostate


  • Prostatic fluid - a milky, slightly acidic fluid (pH about 6.5) that contains several substances
• Bulbourethral Glands


  Or Cowper's Glands. During sexual arousal, it secretes an alkaline fluid into the urethra that protects the passing sperm by neutralizing acids from urine in the urethra
• Semen


  A mixture of sperm and seminal fluid, a liquid that consists of the secretions of the seminiferous tubules, seminal glands, prostate, and bulbourethral glands
• Semen


  • The volume of semen in a typical ejaculation is 2.5–5 milliliters (mL), with 50–150 million sperm per mL. When the number falls below 20 million/mL, the male is likely to be infertile. A very large number of sperm is required for successful fertilization because only a tiny fraction ever reaches the secondary oocyte, whereas too many sperm without sufficient dilution from seminal fluid results in infertility because the sperm tails tangle and lose mobility
  • Despite the slight acidity of prostatic fluid, semen still has a slightly alkaline pH of 7.2–7.7 due to the higher pH and larger volume of fluid from the seminal glands
  • Once ejaculated, liquid semen coagulates within 5 minutes due to the presence of clotting proteins from the seminal glands
  • Capacitation - After passing through the uterus and uterine tube, the sperm are affected by secretions of the uterine tube in a process
  • Hemospermia - the presence of blood in the semen
• Penis


  Contains the part of the spongy urethra and is a passageway for the ejaculation of semen and the excretion of urine
• Penis


  • Body of the penis - is composed of three cylindrical masses of tissue, each surrounded by dense irregular connective tissue called the tunica albuginea
  • The two dorsolateral masses are called the corpora cavernosa penis. The smaller midventral mass, the corpus spongiosum penis, contains the spongy urethra and keeps it open during ejaculation
  • Glans penis - The distal end of the corpus spongiosum penis is a slightly enlarged, acorn-shaped region. Its margin is the corona
  • External urethral orifice - The distal urethra enlarges within the glans penis and forms a terminal slitlike opening
  • Prepuce - covering the glans in an uncircumcised penis
  • Root of the penis - is the attached portion (proximal portion)
  • Bulb of the penis - the expanded posterior continuation of the base of the corpus spongiosum penis
  • Crura of the Penis - the two separated and tapered portions of the corpora cavernosa penis
  • The weight of the penis is supported by two ligaments that are continuous with the fascia of the penis. (1) The fundiform ligament arises from the inferior part of the linea alba. (2) The suspensory ligament of the penis arises from the pubic symphysis
  • Erection - the enlargement and stiffening of the penis
  • Sexual Intercourse - the insertion of the erect penis into the vagina
  • Priaprism - refers to a persistent and usually painful erection of the penis that does not involve sexual desire or excitement
  • Ejaculation - the powerful release of semen from the urethra to the exterior, is a sympathetic reflex coordinated by the lumbar portion of the spinal cord
  • Emission - the discharge of a small volume of semen before ejaculation. Emission may also occur during sleep (nocturnal emission). The musculature of the penis (bulbospongiosus, ischiocavernosus, and superficial transverse perineal muscles), which is supplied by the pudendal nerves, also contracts at ejaculation
• Major Parts of Sperm

  • Head - the flattened, pointed part of the sperm, measuring about 4-5 μm long. Acrosome is a caplike vesicle filled with enzymes, which helps the sperm penetrate the secondary oocyte during fertilization. It covers the anterior ⅔ of the nucleus
  • Tail - responsible for propelling the sperm toward the egg. It is subdivided into four parts: Neck, Middle piece, Principal piece, End piece
• Gynecology


  The specialized branch of medicine concerned with the diagnosis and treatment of diseases of the female genital system
• Functions of the Female Genital System

  • The ovaries produce secondary oocytes and hormones, including progesterone and estrogens (female sex hormones), inhibin, and relaxin
  • The uterine tubes transport a secondary oocyte to the uterus and normally are the sites where fertilization occurs
  • The uterus is the site of implantation of a fertilized ovum, development of the fetus during pregnancy, and labor
  • The vagina receives the penis during sexual intercourse and is a passageway for childbirth
  • The mammary glands synthesize, secrete, and eject milk for nourishment of the newborn
• Ovaries


  The female gonads, are paired glands that resemble unshelled almonds in size and shape; they are homologous to the testes
• Ovaries


  • Broad Ligament - which is a fold of the parietal peritoneum, attaches to the ovaries by a double-layered fold of peritoneum called the mesovarium
  • Ovarian ligament
• Gynecology


  Diagnosis and treatment of diseases of the female genital system
• Functions of the Female Genital System

  • Ovaries produce secondary oocytes and hormones
  • Uterine tubes transport secondary oocyte to uterus and site of fertilization
  • Uterus is site of implantation, fetal development, and labor
  • Vagina receives penis during intercourse and is passageway for childbirth
  • Mammary glands synthesize, secrete, and eject milk
• Ovaries


  • Paired glands resembling unshelled almonds in size and shape, homologous to testes
  • Broad ligament attaches ovaries
  • Ovarian ligament anchors ovaries to uterus
  • Suspensory ligament attaches to pelvic wall
  • Hilum is point of entrance and exit for blood vessels and nerves
• Histology of the Ovary


  • Ovarian mesothelium (surface epithelium)
  • Tunica albuginea (whitish capsule of connective tissue)
  • Ovarian cortex
  • Ovarian medulla
  • Ovarian follicles (containing oocytes and follicular/granulosa cells)
  • Tertiary ovarian follicle (Graafian follicle)
  • Corpus luteum (remnants of tertiary follicle after ovulation)
• Uterine Tubes


  • Also called fallopian tubes or oviducts, extend laterally from uterus
  • Infundibulum (funnel-shaped portion near ovary)
  • Ampulla (widest, longest portion)
  • Isthmus (short, narrow, thick-walled portion joining uterus)
  • Peg cells (ciliated and nonciliated columnar epithelial cells)
• Uterus


  • Normally in anteflexion position over bladder
  • Broad ligaments, uterosacral ligaments, cardinal ligaments, and round ligaments attach uterus to pelvic cavity
• Histology of the Uterus

  • Perimetrium (outer serous layer)
  • Vesicouterine pouch (anterior reflection of peritoneum)
  • Rectouterine pouch (posterior reflection of peritoneum)
  • Myometrium (middle muscular layer)
  • Endometrium (inner mucosal layer)
  • Uterine arteries and veins