Transcript Slide 1
Epididymis • Functions: – Main site of absorption of excess fluid produced by ST – Site of accumulation and storage of spermatozoa – Site of maturation of spermatozoa Vas Deferens • Continuation of the ductus epididymis (at the most inferior portion of the tail of the epididymis) • Embedded in the spermatic cord Spermatic Cord • Consists of several structures which enter and leave the testis and are bundled together by CT – – – – Vas deferens + artery and vein Testicular artery Pampiniform plexus of veins Lymphatics and nerves of testis Spermatic Cord • Structures within are enveloped by 3 layers of tough CT – Internal spermatic fascia – Cremasteric fascia – longitudinally arranged striated muscle fibers (cremasteric muscle) – External spermatic fascia Vas Deferens • 3 layers: – Mucosa • Thrown into folds that give the lumen a highly irregular shape • Pseudostratified epithelium with stereocilia • Lamina propria: loose CT – Muscularis: smooth muscle (3 layers) – Adventitia • Ampulla – distal dilated segment of vas deferens, lined by simple columnar or pseudostratified epithelium Ejaculatory Ducts • Formed by the union of the vas deferens with the duct of the seminal vesicle (before the VD enters the prostate gland) • Penetrates the prostate gland • Empties into the posterior part of the prostatic urethra Ejaculatory Ducts • Mucosa: – Exhibit folds – Simple columnar epithelium • No muscular layer Urethra • Prostatic urethra • Membranous urethra • Spongy urethra Penis • Male copulatory organ • Grossly: root and body (shaft) • Consists of 3 cylindrical cavernous bodies bound together by CT and covered externally by skin – Corpora cavernosa (2) – Corpus spongiosum Penis • Corpora cavernosa (2) – Dorsum of penis – Corpus spongiosum – On the medial plane – Ventral to corpora cavernosa – Enlarged distal portion forms a conical structure (glans penis) covered by a fold of skin (prepuce) – Central portion occupied by spongy urethra Cavernous Bodies • Made up of erectile tissue – Made up of anastomosing blood channels that are ordinarily collapsed – Rapidly fill up with blood under the influence of erotic stimuli Penis • Cavernous bodies enclosed by tunica albuginea • Skin: no hair follicles, limited number of sweat glands • Sebaceous glands of Tyson – atypical sebaceous glands found in undersurface of prepuce and proximal portion of glans penis • Smegma – accumulation of secretions of the glands of Tyson betrween the prepuce and glans penis Accessory Glands • Prostate gland • Seminal vesicles • Bulbourethral glands of Cowper Accessory Glands • Combined secretions account for most of the volume of the male ejaculate or semen (2-5 mL) – 10 % sperm cells (20-50 million) – 60 % seminal vesicles – 30 % prostate gland Prostate Gland • Largest accessory gland • Chestnut-shaped organ • Lies immediately under the apex of the urinary bladder • Substance is traversed by the prostatic urethra Prostate Gland • Covered by dense CT capsule • Composed of 50 poorlydefined lobules divided by CT septa • Fibromuscular organ – capsule and septa are richly supplied with smooth muscle fibers, collagenous fibers and fibroblasts Prostate Gland • 3 groups of tubuloalveolar glands: all open into the prostatic urethra – Prostatic glands – Submucosal glands – Mucosal glands Prostate Gland • Alveoli: lined with simple squamous, simple cuboidal, simple columnar, and pseudostratified columnar epithelium • Corpora amylacea – small lamellated concretions found in the lumen of some of the alveoli • Secretion of prostate gland – Alkaline – Contains enzymes, fibrinolysin, prostaglandin, and a compound with antibiotic properties Seminal Vesicles • Paired, sac-like structure, 5 cm long • Lies between the fundus of the bladder and rectum, above the prostate gland • Long, coiled, narrow tube covered by a vascular CT capsule Seminal Vesicles • 3 histologic layers: – Mucosa • Forms folds that give the lumen a maze-like appearance • Non-ciliated pseudostratified columnar epithelium • Composed of lipochrome pigment granules – Muscularis: OLIC – Adventitia Seminal Vesicles • Secretion contains: – Fructose – energy source for spermatozoa – Prostaglandins – Fibrinogen Bulbourethral Glands of Cowper • Pair of pea-sized (1 cm), yellowish organs • Lie at the back of and lateral to membranous urethra (embedded in the fibers of the sphincter urethrae muscle) • Consists of a single, long duct (2.5-3.0 cm) that opens into the proximal portion part of spongy urethra Bulbourethral Glands of Cowper • Compound tubuloalveolar mucus-secreting gland • Enclosed by a thin CT capsule • Consists of lobules divided by CT septa • Alveoli: simple cuboidal epithelium • Ducts: – Initial: simple columnar epithelium – Main duct: pseudostratified epithelium