The two main biological functions of the male reproductive system are: 1) The production of sperm. Sperm is the male reproductive cell. 2) The transfer of sperm into the female’s body during sexual intercourse.
LifeArt image copyright 2007 Lippincott Williams & Wlikins. All Rights Reserved.
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Male Reproductive System Male External Organs
Testes, also known as testicles, are two small glands that produce sperm. They produce sperm at a rate of 100 million per day. The sperm resemble tadpoles and are so tiny that if you were to line up 500 of them it would only measure 1 inch.
LifeArt image copyright 2007 Lippincott Williams & Wlikins. All Rights Reserved.
Male Reproductive System Male External Organs
The testes hang outside the body in a sac known as the scrotum. The scrotum helps protect the sperm by ensuring that the testes remain at a temperature slightly below the normal body temperature of 98.6°F (37°C). If a male's body temperature rises, the muscles of the scrotum relax so that the testes are held away from the body. If his body temperature drops, the muscles contract, which pull the testes closer to the body.
LifeArt image copyright 2007 Lippincott Williams & Wlikins. All Rights Reserved.
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Male Reproductive System Male External Organs
The penis is a tube-shaped organ attached to the trunk of the body just above the testes. The penis is composed of spongy tissue that contains numerous blood vessels. Increased blood flow enlarges and erects the penis. Males of every age experience erections, and these can occur for no reason at all.
LifeArt image copyright 2007 Lippincott Williams & Wlikins. All Rights Reserved.
Male Reproductive System Ejaculation
Erections usually occur as the result of becoming sexually aroused. At the height of sexual arousal, a series of muscular contractions known as ejaculation may occur. During ejaculation semen, a thick fluid containing sperm and other secretions from the male reproductive organs, is propelled from the penis.
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Male Reproductive System Ejaculation
If this happens during sexual intercourse, fertilization may take place. Fertilization is the union of a sperm (from a male) and an ovum (from a female). A fertilized egg can then grow inside the female to become a baby.
LifeArt image copyright 2007 Lippincott Williams & Wlikins. All Rights Reserved.
Male Reproductive System Ejaculation
It is also normal for males to experience wet dreams. This is when a male becomes erect and ejaculates during his sleep.
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Male Reproductive System Male Internal organs
The male internal reproductive organs include:
The epididymis The vas deferens The seminal vesicles The prostate gland The Cowper’s glands The urethra
LifeArt image copyright 2007 Lippincott Williams & Wlikins. All Rights Reserved.
Male Reproductive System Male Internal organs
The epididymis stores sperm cells while they mature.
LifeArt image copyright 2007 Lippincott Williams & Wlikins. All Rights Reserved.
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Male Reproductive System Male Internal organs
The vas deferens propels sperm forward toward the seminal vesicles and the prostate gland just before ejaculation.
LifeArt image copyright 2007 Lippincott Williams & Wlikins. All Rights Reserved.
Male Reproductive System Male Internal organs
The seminal vesicles are glands that produce fluid, which contains nutrients and allows the sperm more mobility. The vas deferens and the seminal vesicles meet to form the ejaculatory duct, where the fluid combines with sperm.
LifeArt image copyright 2007 Lippincott Williams & Wlikins. All Rights Reserved.
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Male Reproductive System Male Internal organs
The prostate gland is a small gland that surrounds the urethra. It produces fluid that helps make up semen.
LifeArt image copyright 2007 Lippincott Williams & Wlikins. All Rights Reserved.
Male Reproductive System Male Internal organs
The Cowper’s glands are located below the prostate gland, and they also produce fluid that helps make up semen. The fluid helps to neutralize the acidic environment of the female reproductive organs before semen is ejaculated. LifeArt image copyright 2007 Lippincott Williams & Wlikins. All Rights Reserved.
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Male Reproductive System Male Internal organs
The urethra is a passageway for both semen and urine to leave the body. Semen and urine do not leave the body at the same time. A muscle near the bladder contracts when semen is present in order to prevent urine from entering the urethra. LifeArt image copyright 2007 Lippincott Williams & Wlikins. All Rights Reserved.
