1. The Male Reproductive System Chapter 2 – Lesson 1

2. What is the function of the Male Reproductive System? To produce A sperm cell Unite with the female egg To form a fertilized ovum

3. External Male Organs  Testes: Male sex glands  2 function: manufacture the male sex hormone, testosterone  Produce male reproductive cells, sperm  Scrotum: Sac that hangs outside the body and holds the testes.  Penis: Tube-like organ that functions in sexual reproduction, sexual pleasure, and elimination of body wastes.

4. Scrotum  Function: Keeps the testes at the right temperature so they can produce sperm.  Temperature must be 3 – 4 degrees F lower than normal body temperature of 98.6 degrees to produce sperm.  If Temp muscles in the scrotum relax away from the testes  If Temp muscles in the scrotum contract to pull the testes closer to the body.

5. Testes  Sperm are produced in a section of the testes called seminiferous tubules ( Long series of threadlike tubes )  There are about 1000 of these tubes, each about 1-3 ft. long.  Combined length = one-half mile  Capable of producing billions and billions of sperm.  Testes produce 500 million or more sperm each day.

6. The Sperm Cell Size:.0024 inch, or 60/10,000 millimeter, long.

7. Epididymis (over the testes)  Where sperm move once produced.  A highly coiled structure located on the back side of each of the testes.  About 20 ft. in length.  The maturation of sperm (which being in the seminiferous tubules) continues here.  Takes about 64 days from the time sperm are produced to fully mature.

8. The Penis  Made up of 3 long cylinders of spongy tissue that line parallel to the urethra.  Contain a very rich supply of blood vessels.  When soft, cylinders contain little blood.  When blood from circulatory system fills these spaces, becomes hard – or erect.  Neither a bone or a muscle.

9. Circumcision  All male babies are born with a fold of skin that covers the end of the penis – foreskin  Circumcision is the surgical removal of the foreskin.  Smegma: made up of dead cells and glandular secretions, can get trapped under the foreskin.

10. Internal Male Reproductive Organs  The Vas Deferens  The Seminal Vesicles  The Prostate Gland  The Cowper’s Glands  The Urethra

11. Vas Deferens After the sperm mature in the Epididymis – they travel to the Vas deferens. Two tubes, each 18 in. long Lined with cilia, fingerlike projections That help move the sperm Loops over the pubic bone, around The bladder, and through the prostate gland. Ejaculatory duct opens up into urethra.

12. Seminal Vesicles  Two little pouches that sit above and on either side of the prostate gland.  “fluid-filled pouch”  Secrete a fluid that mixes with the sperm.  Helps the sperm become mobile and provides nourishment.

13. The Prostate Gland  Lies just below the bladder and surrounds the urethra.  Size of a chestnut  Secretes a milky, alkaline fluid that mixes with sperm and makes up the major portion of semen.  It is the solution that helps protect the sperm – neutralizing acidity of vagina in female.

14. The Cowper’s Gland  Just below prostate  Two pea-sized glands open up into the urethra.  Secrete a clear, sticky fluid that cleanses the urethra of acid from urine – allowing safe passage for sperm.  Some fluid is released before semen, forming at the end of the penis before ejaculation – can contain sperm.

15. Urethra  Tube-like organ that travels through the penis.  Serves as a passageway for sperm and urine.  When semen is preparing the leave the body, special muscles contract to close off bladder.  Urine cannot leave when semen leaves

16. Pathway of Sperm

17. Semen  Fluids from the Seminal Vesicles + Prostate Gland + Cowper’s Glands = Semen.

18. Bladder Rectum Scrotum Testes Epididymis Vas Deferens Prostate Penis Urethra Cowper’s Gland Seminal Vesicles