Male Reproductive System Histology Summary PDF

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Male Reproductive System Histology SummaryGross Anatomy Testis Located in the Scrotum, tunica vaginalis (mesothelium sac, peritoneum) o Seminiferous tubules - Produce Sperm o Interstitial Cells - Produce Androgens  Epididymis - Sperm Storage  Vas Deferens - Duct, transports Sperm from testis to t...

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1 Male Reproductive System Histology Summary Gross Anatomy       

Testis Located in the Scrotum, tunica vaginalis (mesothelium sac, peritoneum) o Seminiferous tubules - Produce Sperm o Interstitial Cells - Produce Androgens Epididymis - Sperm Storage Vas Deferens - Duct, transports Sperm from testis to the Prostate Gland Seminal Vesicle - Secrets Fluid, rich in Fructose, part of Semen Prostate Gland (Ejaculatory Duct) Milky Alkaline Fluid (assists Sperm Activation) Cowpers Gland [Bilbourethral Gland] - Contributes Mucus to Semen Urethra (Penis) - Organ of Copulation

Histology of the Male Reproductive System Testis Structure

Seminiferous tubules

– Oval structure (5x3cm)  Surrounded by tough white dense fibromuscular connective tissue Capsule - Tunica Albuginia,  divided into 250 lobes by fibrous connective tissue (septa)  Each lobule contains 1 to 4 highly coiled seminiferous tubules that converge to form a single straight tubule, which leads into the rete testis.  Interstitial cells (cells of Leydig), which produce male sex hormones, are located between the seminiferous tubules within a lobule. Sertoli Cells (within the seminiferous tubules) provide support and nutrition for the sperm.

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Rete Testis (Anastomosing cuboidal epithelial network of tubules in posterior testes near epididymis)

Testicular Tubule, Duct System  Spermatozoa pass via the tubuli recti (low columnar epithelium) and the rete testis (flattened or cuboidal epithelium) into numerous ductuli efferentes, which are lined by a columnar epithelium, which consists of both absorptive and ciliated cells.  Ductus Efferentes  10-20 tubules connecting to Epididymis  Mixed Ciliated and Non Ciliated Cuboidal epithelium  Ciliated Cuboidal epithelium, Cilia beat toward Epididymis  Non Ciliated Cuboidal epithelium, Absorb fluid secreted by Seminiferous Tubules  Smooth muscle layer, thin, outside epithelium 

Epididymis, outside testis, sperm storage and maturation  Coiled tube, 4-6 meters long  Pseudostratified Columnar epithelium (2 layer of nuclei)  stereocillia - Long, branched microvilli

Epididymis

Vas Deferens - Duct, transports Sperm from testis to the Prostate Gland  The mucosa of the vas deferens forms low longitudinal folds  Lined by a pseudostratified columnar epithelium. Similar to the epididymis, cells have long stereocilia.  The lamina propria is unusually rich in elastic fibres  The muscularis is well developed (up to 1.5 mm thick) and consists of a thick circular layer of smooth muscle between thinner inner and outer longitudinal layers. The muscularis is the structure which makes the vas deferens palpable in the spermatic cord.  The vas deferens is surrounded by an adventitia, which is slightly denser than usual. Straight Tube

Seminal Vessicle - Secrets Fluid, rich in Fructose, 70% of Semen

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The seminal vesicles develop from the vas deferens They are elongated sacs (about 4 cm long and 2 cm wide), which taper where they unite with the vas deferens. Each seminal vesicle consists of one coiling tube (about 15cm long). Mucosa  Folded  Pseudostratified Columnar epithelium  Low columnar or Long cuboidal  Rich in secretory Granules Lamina propria, elastic fibers Smooth muscle layer, thin Adventitia

Prostate Gland (Ejaculatory Duct) Milky Alkaline Fluid (assists Sperm Activation)  About 2 × 3 × 4 cm). Doughnut-shaped gland that encircles part of the urethra inferior to the bladder  Plays a role in the activation of sperm  Enters the prostatic urethra during ejaculation  It contains 30 - 50 tubuloalveolar glands, which empty into 15 - 25 independent excretory ducts. These ducts open into the urethra. The glands are embedded into a fibromuscular stroma, which mainly consists of smooth muscle separated by strands of connective tissue rich in collagenous and elastic fibres. The muscle forms a dense mass around the urethra and beneath the fairly thin capsule of the prostrate.  Epithelium, mostly columnar with a few basal cells

Prostate gland

Urethra (Penis) 1. Prostatic urethra a. Pseudostratifed Columnar Epithelium

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4 b. Mucosal and submucosal glands hypertrophy with age 2. Membranous urethra a. Stratified columnar epithelium b. surrounded by striated muscle 3. Spongiosa urethra a. Stratified squamous b. Mucous glands Cowpers Gland [Bilbourethral Gland]  Pea-sized glands inferior to the prostate  Produce alkaline mucus prior to ejaculation that neutralizes traces of acidic urine in the urethra

Penis The penis has a root, body (shaft), and glans penis. The root of the penis attaches it to the pubic arch and the body is the visible, pendant portion. The corpus spongiosum expands at the distal end to form the glans penis. The urethra, which extends throughout the length of the corpus spongiosum, opens through the external urethral orifice at the tip of the glans penis. A loose fold of skin, called the prepuce, or foreskin, covers the glans penis. Penis cross section

Tissues to be reviewed in microanatomy lab: Testes, vas deferens, prostate, seminal vessicles

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