Male reproductive system (human)
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|Male reproductive system (human)|
|Drawing of the Male Internal Sexual Anatomy|
|Latin||systema genitale masculinum|
The human male reproductive system (or male genital system) consists of a number of sex organs that are a part of the human reproductive process. In this type of reproductive system, these sex organs are located outside the body, around the pelvic region.
The main male sex organs are the penis and the testes which produce semen and sperm, which as part of sexual intercourse fertilize an ovum in female's body and the fertilized ovum (zygote) gradually develops into a fetus, which is later born as a child.
External genital organs
The penis is the male copulatory organ. It has a long shaft and enlarged bulbous-shaped tip called the glans penis, which supports the foreskin. When the male becomes sexually aroused, the penis becomes erect and ready for sexual activity. Erection occurs because sinuses within the erectile tissue of the penis become filled with blood. The arteries of the penis are dilated while the veins are passively compressed so that blood flows into the erectile cartilage under pressure. [File:Not Fully Erect Human Penis.png|thumb|Not Fully Erect Human Penis]
The scrotum is a pouch-like structure that hangs behind the penis. It holds and protects the testes. It also contains numerous nerves and blood vessels. During times of lower temperatures, the Cremaster muscle contracts and pulls the scrotum closer to the body, while the Dartos muscle gives it a wrinkled appearance; when the temperature increases, the Cremaster and Dartos muscles relaxes to bring down the scrotum away from the body and remove the wrinkles respectively. The scrotum remains connected with the abdomen or pelvic cavity by the inguinal canal. (The spermatic cord, formed from spermatic artery, vein and nerve bound together with connective tissue passes into the testis through inguinal canal.)
Internal genital organs
The epididymis is a whitish mass of tightly coiled tubes cupped against the testicles. It acts as a maturation and storage place for sperm before they pass into the vas deferens, tubes that carry sperm to the ampullary gland and prostatic ducts.
The vas deferens, also known as the sperm duct, is a thin tube approximately 43.2 centimetres long that starts from the epididymis to the pelvic cavity.
Three accessory glands provide fluids that lubricate the duct system and nourish the sperm cells. They are the seminal vesicles, the prostate gland, and the bulbourethral glands (Cowper glands).
Seminal vesicles are sac-like structures attached to the vas deferens at one side of the bladder. They produce a sticky, yellowish fluid that contains fructose. This fluid provides sperm cells energy and aids in their motility. 70% of the semen is its secretion.
The prostate gland surrounds the ejaculatory ducts at the base of the urethra, just below the bladder. The prostate gland is responsible for the production of semen, a liquid mixture of sperm cells, prostate fluid and seminal fluid.This gland is also responsible for making the semen milky by mixing calcium to the semen coming from seminal vesicle(semen coming from seminal vesicle is transparent in colour),this process is called profibrinolysin .28 to 29% semen comprises its secretion.
The bulbourethral glands, also called Cowper glands, are two small glands located on the sides of the urethra just below the prostate gland. These glands produce a clear, slippery fluid that empties directly into the urethra. It produces substances related to nourishment of spermatozoa.
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