Lesson Plan - Get It!
Do you know how to swim? It's rarely a matter of life and death, but for sperm, it's a race for future generations!
The male sex cell is the sperm, capable of mobility with the help of a motorized tail.
These small cells are continuously produced in large numbers throughout the life of a human male, once puberty is reached. In the previous Related Lesson in our Reproductive System series, found in the right-hand sidebar, you learned about the female reproductive structures that are held in the pelvis. The male reproductive system is found inside and outside of the pelvis.
The male reproductive system contains the testicles, glands, a duct system, and the penis. Unlike the female reproductive system, males also pass urine through reproductive structures.
Once a male has passed through puberty and reached sexual maturity, he produces sperm in the testicles. Males have two testes, structures that produce and store sperm located outside of the pelvis and stored in the scrotum. Testicles, or testes, produce the male sex hormone testosterone. This hormone causes males to have a deeper voice and more body hair than females.
Also located in the scrotum are two tubes that transport sperm through the male reproductive system. The epididymis is a bundle of tubes that connects the testes to the vas deferens, a muscular tube that allows the movement of semen, a fluid containing high numbers of sperm cells.
Additional glands in the male body help produce the components of semen. The prostate gland and seminal vesicles are called accessory glands because they add fluids to the semen. Seminal vesicles are found near the bladder, attached to the vas deferens. The prostate gland is found below the bladder and attached to the urethra, the tube that carries urine and semen out of the body.
The urethra runs from the bladder to the tip of the penis, and is considered part of the excretory system because it removes urine from the bladder. The shaft of the penis is the larger part of the penis, running from the body to the glans, or tip, of the penis. A small opening at the end of the glans allows for semen and urine to leave the body. The penis can expand and contract based on blood flow directed to the structure.
When boys are born, they have a foreskin covering the glans of the penis. This is a covering of skin that some boys have removed during circumcision, a procedure where the foreskin is cut away. For many families, the decision to circumcise is religious, but others claim that it improves hygiene.
The male reproductive system revolves around the production and release of semen, a fluid containing sperm cells. Sperm is produced in the testicles, and stored until the body prepares for release. Fluids from the accessory glands are added to create semen. Semen travels through the urethra, running the length of the penis, before release.
- Why do you think that additional fluids are added to the sperm cells?
- What role do hormones play in the male reproductive system?
In the Got It? section, you will learn more about the production of sperm and semen as it travels through the male reproductive system.