The Male Reproductive System By: Zephaniah Molina, Jacqie Schieffer, and Scott Schramm

The Penis The penis is the male reproductive organ, and it can be used for two purposes. 1. Urination 2. Ejection of semen In males, urination is done through the urethra of the penis. The urine first goes to the prostate gland, where it then goes to the ejaculatory gland. Then onward, it makes its way to the penis. Ejaculation is the ejecting of semen from the penis. A series of muscular contractions delivers semen, containing male gametes known as sperm cells or spermatozoa, from the penis. It is usually the result of sexual stimulation.

Structure The male reproductive system differs from the female reproductive system because it is located outside of the body. Its structure includes the penis, scrotum, and testicles. The penis is the male organ used in sexual intercourse which has three main parts: the root that attaches to the abdomen, the shaft, and the glans. Some men are circumcised, meaning the removal of foreskin covering the head of the penis. The foreskin is the continuation skin of the shaft that helps protect the penis, aid in sex, and keep the penis healthy with oils. The scrotum, loose skin that hangs behind the penis, contains the testes. The testicles (testes) are responsible for making the male sex hormone, testosterone, in which sperm continuously generates 50,000 per minute.

Structure (cont’d) The Corpus Cavernosum is an erectile tissue that surrounds the urethra that is part of the shaft. When sexual aroused, blood rushes to these tissues forming the erection. The Corpus Spongiosum surrounds the urethra. It prevents the urethra from being closed while in an erect state. without this while in an erect form, sperm would not be able to pass though.

Spermatic Duct System The Duct System is comprised of the epididymis, vas-deferens, seminal vesicle, Cowper's gland, and prostate gland. The epididymis stores the spermatozoa and this is where it matures for some time it is located next to the testicle. Vas-deferens is a tube that connects the spermatozoa flowing through the epididymis with the ejaculatory duct Seminal vesicle contains seminal fluid. The ejaculatory duct is the point where the seminal vesicle and vas- deferens meet, which go though the prostate and into a small opening in the urethra. The prostate gland gives out a light alkaline fluid that also adds to the semen. Cowper’s gland or bulbourethral gland are released first before ejaculation which makes a lubricant. This lubricant is also know as pre-ejaculation.

How it Looks

Sperm Sperm needs to stay at a certain temperature that is 4-5 degrees lower them the regular body temperature. When colder then usual, the scrotum will contract to bring the testes closer to the body thus raising the temperature. When ejaculated out, it is mixed with fluids coming from various glands which makes up its texture, help it survive out of the body, and provides energy for it The head of the sperm holds the genetic information. The middle holds mitochondria used to generate ATP for movement. And the tail is a flagella used for propulsion. It also has an enzyme used to break down the wall of the egg to deliver the genetic information. It takes about 2-3 months to fully mature sperm. When maturing, it stays in the epididymis for 1-3 weeks as the final step.

The structure of the sperm

Erectile Dysfunction Erectile Dysfunction is a disease in which blood does not flow through the penis and will cause an inability for an erection. A penile erection is the hydraulic effect of blood entering and being retained in sponge-like bodies within the penis. The process is often initiated as a result of sexual arousal, when signals are transmitted from the brain to nerves in the penis. Any compression of nerves and blood to the penis can result in temporary ED. A form of treatment that is most common, pharmaceuticals, can be found in many different forms. When pharmacological methods fail, a purpose-designed external vacuum pump can be used to get an erection, with a separate compression ring fitted to the penis to maintain it.

As men age, it is more common to develop erectile dysfunction as seen in this graph.

Bibliography Male Reproductive System. Perf. Dr.Fabian. Www.youtube.com. Youtube, 9 Dec. 2008. Web. 6 May 2013. <http://www.youtube.com/watch?v=j0ziehdvjbc>. Parker, Steve. "Male Reproductive System." The Human Body Book. New York: DK, 2007. 202-03. Print. Taylor, Tim. "Male Reproductive System." InnerBody. InnerBody, 1999. Web. 10 May 2013. <http://www.innerbody.com/image/repmov.html>.