topic 11 pt 1

• What is the primary function of the scrotum in the male reproductive system?

  It contains and protects the testes.

  
• How does the internal septum of the scrotum function?

  It divides the scrotum into two sacs, each containing one testis.
• What are the two important muscles found in the scrotum?

  Cremaster muscle and Dartos muscle.
• What is the role of the cremaster muscle?

  It contracts to pull the testes closer to the body in cold conditions.
• What does the Dartos muscle do in response to cold temperatures?

  It wrinkles the scrotal skin.
• What does the spermatic cord consist of?

  Testicular artery, testicular vein, testicular nerves, ductus deferens, and pampiniform plexus.

  
• What is the function of the pampiniform plexus?

  It acts as a radiator to prevent excess heat from reaching the testis.
• What is the Countercurrent Heat Exchange Mechanism?

  It maintains a temperature 2-3°C cooler for correct sperm production.
• What are the testes?

  Paired oval-shaped glands that make sperm and testosterone.
• What covers the testes?

  The tunica albuginea, a white fibrous coat.

  
• How does the tunica albuginea affect the testes?

  It penetrates and divides each testis into 250 lobules.
• What do seminiferous tubules do?

  They are where sperm cells are made.
• How long can seminiferous tubules be?

  Each can be up to 70 cm long, totaling about 1 km of tubing.
• What do seminiferous tubules join to form?

  The tubulus rectus, which unites as the rete testis.

  
• What is the pathway of sperm after leaving the testis?

  Sperm leave through the efferent ductules into the epididymis, then the ductus deferens.

  
• What is the function of the efferent ductules?

  They sweep non-motile spermatozoa into the epididymis.

  
• What are the parts of the epididymis?

  Head, body, and tail.
• What type of epithelium lines the epididymis?

  Pseudostratified columnar epithelium with stereocilia.
• What is the role of the epididymis in sperm maturation?

  It is the site for the final maturation of sperm.
• What must happen for sperm to become fully functional and motile?

  They must be mixed with seminal secretions and exposed to conditions in the female reproductive tract.
• What are Sertoli cells also known as?

  Nurse cells or sustentacular cells.
• What is the function of Sertoli cells?

  They nourish all cells within the seminiferous tubules and secrete ABP and inhibin.
• What do tight junctions between Sertoli cells form?

  The blood-testis barrier.
• What is the role of the blood-testis barrier?

  It prevents developing sperm from escaping into the bloodstream.
• What are interstitial cells also known as?

  Leydig cells.
• What is the primary function of interstitial cells?

  They are the source of testosterone (95%).
• What does the ductus deferens do?

  It stores sperm and propels them toward the urethra during ejaculation.
• What forms the ejaculatory duct?

  The union of the ducts from the seminal vesicles and vas deferens.
• Where does sperm and seminal fluid combine?

  In the ejaculatory duct before moving into the prostatic urethra.
• What type of epithelium lines the ductus deferens?

  Pseudostratified columnar epithelium with stereocilia.
• What surrounds the ductus deferens?

  Thick smooth muscle.
• How long is the urethra?

  About 20 cm long.
• What does the urethra carry?

  Both seminal fluid and urine, but not both at the same time.
• What are the three parts of the urethra?

  Prostatic urethra, membranous urethra, and spongy/penile urethra.
• What do seminal vesicles produce?

  Approximately 60% of seminal fluid.
• Where are the seminal vesicles located?

  On the posterior of the bladder.
• What does the prostate gland account for in seminal fluid production?

  30% of seminal fluid.
• What do bulbourethral glands secrete?

  A thick alkaline mucus that lubricates the glans penis.
• What is the function of the alkaline mucus secreted by bulbourethral glands?

  It removes trace levels of acidity in the urethra before ejaculation.
• What are some components of seminal fluid?

  Clotting factors, fructose, citric acid, prostaglandins, and PSA.