ANP 1107 - Male Reproductive System Flashcards
SCROTUM
- Hangs outside the abdominal cavity
- Contains testes
- Divided by septum
- 3 degrees lower
Dartos Muscle (scrotum)
Smoot muscle
Cremaster Muscle (scrotum)
Skeletal muscle
Testes: Tunics
Tunica Vaginalis: two layers, derived from the peritoneal cavity
Tunica Albuginuea: fibrous capsule of the testes
Testes
- Each on contains 250 lobules
- —-Each lobule contains 1-4 seminiferous tubules
Testes: Leydig cells
- Found in soft connective tissue surrounding seminiferous tubules
- Produce ANDROGENS
Testicular Artery
- From abdominal aorta –> pelvis
- Supply testes
Testicular Veins
- From paminiform venous plexus
- Surrounds the testicular artery within the scrotum
- Absorbs heat from arterial blood, cooling it
Testes: Spermatic Cord
- Blood, lymph vessels, nerves
Sperm in Epididymis
Seminiferous tubules –> Tubulus Rectus –> Rete Testes –> Efferent ductiles –> epididymis
Epididymis
- Cup shaped
- 3.8 cm long
- Head contains efferent ductules
- Sperm enters immature and immobile
- 20 days later can swim
- Sperm regenerates every 2-3 months
Vas Deferense
- Carries away
- 45 cm long
- From epididymis to lingual canal into pelvic cavity
- CUT THIS FOR VESECTOMY
Vas Deferense: mucosa epithelium
- Pseudostratistfied
Urethra
- Terminal portion of male duct system
Prostatic Urethra
- Surrounded by the prostrate
Membranous Urethra
- Urogenital diaphragm
Spongy Urethra
- Through penis
- 75% of urethral length
Glands
- 2 seminal vesicles
- 2 bulboureathral glands
- Prostate glands
- Produce bulk of semen
Seminal Vesicles Glands
- Posterior to bladder surface
- 5-7 cm long
- Contracts during ejaculation
- 70% of semen
Musocal Cypts in Seminal Vesicles
- yellow, viscous sugar
- fructose
- sugar
- coagulating enzymnes
- prostaglandins
Prostate Gland
- Encircles urethra
- Inferior to bladder
- Semen enters via ducts when smooth muscles contracts
- 1/3 volume of semen
- Activates sperm
- Milky, acidic
Prostate Gland Composites
- Milky
- Acidic
- Citrate
- Enzymes
- Prostate Specific Antigen (PSA)
Bulbourethral Glands
- Pea sized
- Inferior prostate
- Produces thick clear mucus
- Mucus neutralizes traces of acidic urine
Penis
- Composed of shaft and glans penis
- Contains spongy urethra and three cylindrical bodies
Corpus Spongiousum
Surrounds uretha
Semen
- Milky white fluid
- Mixture of sperm, testicular fluid and accessory gland secretions
- Transports nutrients
- Protects and activates sperm
Relaxin
enhances sperm motility
Semen pH
7.2 - 7.7
Synthesis of Testosterone
Cholesterol –> pregesteron –> androstenedion –> testosterone
Testosterone: Gonadal Actions
- Growth and maturation of gonads and accessory glands during puberty
- Essential for spermatogenesis
Testosterone: Somactic Actions
- Starts: interacts with bone tissue to converts to estrogenic, growth of bones
- Stops: when levels reached, stimulates closure
- Growth of larynx
- Secretion of sweat
- Hair development
Testosterone: Metabolic Actions
Anabolic hematopoiesis BMR
Testosterone: CNS Actions
- Maintenance of Libido
- Agression
Anterior Pituitary Hormones
- GH
- TSH
- ACTCH
- FSH
- LH
- PRL
- PIH
FSH
- Stimulates sertoli cells, supports spermatogenesis
- Regulates the function of gonads
- Stimulates spermatogenesis by stimulating ABP
LH
- Stimulates leydig cells to secrete testosterone
- Stimulates gamete production of gonadal hormones
GnRH
- Controls secretion of FSH and LH
- Released from hypothalamus, reaches cells via blood
- Acts on AP to inhibit gonatropin release
Inhibin
- Release by sertoli cells
- Inhibits only FSH
Forming Spermatocytes
- Spematogonia (stem cells) continuously divide
- Daughter cells, type A and type B
Type A
- Stay at the basal lamina to maintain germ cell line
Type B
- Cells get pushed towards the lumen and become PRIMARY SPERMATOCYTES
Primary Spermatocytes
Undergo meiosis I to form halploid cells to form secondary spermatocytes.
Secondary Spermatocytes
- Continue meiosis II
- Daughter cells are spermatids
Spermatids
- Small round cells
- Large nuclei
- Closer to lumen
- Compact their DNA into dense pallets
Spermatogenesis
- Spermatids to sperm
- Undergo spermatogenesis
- Results in spermatozoon
- — Head
- — Midpeice
- — Tail
Takes 64-72 days
Head of Sperm
- Flattened nucleus
- Contains compact DNA
- Has an acrsome on the top
Acrosome
- Produced by Golgi A
- Contains hydrolytic enzymes that enable sperm to penetrate
Tail
- Flagellum
- Produced by one centriole
- Mitochondria allow the sperm to swim
Sertoli Cells
- Extend from basal lamina to lumen
- Bound by lateral tight junctions
Basal Compartment
Contains spermatogonia and earliest primary spermatocytes
Adluminal Compartment
- Internal to tight junctions
- Includes meiotically active cells and lumen
Leydig Cells
- Between seminiferous tubules
- Vascularized
- Receptor for LH
Blood Testis Barrier
- Tight junction between sertoli cells
- ## prevents membrane antigens from escaping
