Exam 5 Review:  Chapter 27 Male Duct System I

straight tubules - The short, relatively linear connecting ducts, lined by sustentacular cells, between the seminiferous tubules and the rete testis of the testes, through which spermatozoans move on the way to storage and physiological maturation (capacitation) in the epididymus.

rete testis - The interconnecting network of ducts, lined with simple cuboidal epithelium, at the end of the straight tubules which conduct spermatozoa from the testes to the efferennt ducts and on to the epididymis.

efferent ducts - The set of fifteen to twenty ducts, lined with simple epithelium (some tall columnar ciliated cells, some short columnar non-ciliated cells, some basal stem cells), at the end of the rete testis conduct spermatozoa from the testes to the epididymis; the presence of ciliated cells and the presence of some smooth muscle in the walls of these ducts indicate that these ducts are important in actively transports spermatozoa out of the testes and into the epididymis.

High Power View of Efferent Duct

ep = epithelial layer, sm = smooth muscle layer

epididymis - The single highly coiled tube, located on the external surface of each testis, lined by a pseudostratified columnar epithelium, which receive and store spermatozoa produced by the testis; it is divided into three regions, the head, body and tail, and the tail is continuous with the ductus = vas deferens; the epithelial cells secrete a glycocalyx for the sperm and various local hormones required for sperm maturation and also phagocytize degenerate sperm; the head and body are surrounded by a circular layer of smooth muscle which moves sperm along by peristalsis; the tail, which acts as the reservoir for mature sperm, has three, much thicker layers of smooth muscle: an inner and outer longitudinal layer surrounding a middle circular layer; during ejaculation, intense contractions of these layers force the sperm into the vas = ductus deferens.

ductus deferens = vas deferens - The muscular tube which receives spermatozoa from the tail of the epididymus during ejaculation and propels it by peristalsis to the ejaculatory ducts at the juncture with the prostatic urethra; it follows the route of the descent of the testes along the spermatic cord through the inguinal canal into the pelvic cavity; it is lined by a pseudostratified columnar epithelium and has three layers to the muscularis: inner longitudinal, middle circular and outer longitudinal; during ejaculation, intense contractions of these layers force the sperm into the prostatic urethra; the seminal vesicles, an outpocketing of the vas = ductus deferens contributes secretions to help form the seminal fluid.

spermatic cord - A tubular structure, consisting of the vas = ductus deferens and its accompanying arteries, veins, nerves, and lymphatic vessels, and lined externally by the tunica vaginalis, which passes from the abdominal cavity through the inguinal canal down into the scrotum to the back of the testicle.

ejaculatory ducts - The short tubes, formed by the junction of the excretory ducts of the seminal vesicles and the last portion of the vas = ductus deferens, which enter the prostate gland to merge with the prostatic urethra; they are is lined by a pseudostratified columnar epithelium.

vasectomy -The surgical sterilization procedure performed on males under local anesthesia in which a segment of the vas = ductus deferens is removed; several variations in the procedure are available, including some, such as the insertion of valves, meant to render the procedure reversible.

List:

 1. the anatomical structures a spermatozoan must traverse starting with its development and ending with its fertilization of an oocyte. Include the processes it must undergo and the glandular secretions that are added to the spermatozoa on the way.

Sperm Formation & Maturation

Structure Activities seminiferous tubule meiosis and spermatogenesis to produce haploid gamete with the physical form of a spermatozoan rete testis and efferent ducts passive travel only epididymus biochemical/physiological maturation and storage

Ejaculation

Structure Activities vas deferens = ductus deferens peristaltic waves power travel prostatic/membranous/spongy urethra peristaltic waves power travel Accessory Gland Activities seminal vesicles secretions include fructose to provide nutrition for the spermatozoa, and a bicarbonate ions which counteracts the acidity of prostate secretions and the vagina prostate gland secretion is slightly acidic, mucous, and contains citric acid, the natural antibiotic, seminalplasmin, and various enzymes, e.g., acid phosphatase and fibrinolysin, which contribute to successful fertilization bulbourethral glands = Cowper's glands thick alkaline mucous secretion which neutralizes any acid urine in the urethra and contributes to the lubrication for intercourse

Travel For Fertilization

Structure Activities vagina swim by flagellar action out of the coagulated semen and through the mucus plug of the cervix uterus swim by flagellar action upward through the uterus uterine tubes = Fallopian tubes = oviducts swim by flagellar action, assisted by tubular peristalsis, in the search for an egg to fertilize

 6.  the organs and the functions of each organ in the male reproductive system.

Sketch and label:

6. a cross section of the testis. Include the various cell types and their role in male reproduction.

[Note:  This figure fails to label the spermatogonial cells at the periphery of the seminiferous tubule and spermatozoans in the lumen of the seminiferous tubule.]

Include the various cell types and their role in male reproduction.

Cell Type Role In Reproduction interstitial endocrinocytes = interstitial cells of Leydig secrete androgens spermatogonial cells give rise to primary speratocytes by mitosis primary and secondary spermatocytes complete meiotic divisions I & I to produce haploid spermatids early and late spermatids complete spermatogenesis by developing the physical form of a mature spermatozoan spermatozoans upon final maturation and delivery to the female reproductive tract, to fertilize an egg = ovum