Anatomy and Physiology

Your urinary tract helps to get rid of urine (your body’s liquid waste). The kidneys collect unneeded chemicals and water, making urine. Urine travels through the ureters to the bladder. The bladder fills with urine, holding it until you’re ready to release it. The urethra is the canal that carries urine from the bladder out of the body. Signals from the brain tell the sphincter (muscles around the opening of the bladder) when to let urine flow out of the body.

Your urinary tract helps to get rid of your body’s liquid waste. The kidneys collect unneeded chemicals and water, making urine. Urine travels through the ureters to the bladder. The bladder fills with urine, holding it until you’re ready to release it. Signals from the brain tell the sphincter(muscles around the opening of the bladder) when to let urine flow out of the bladder. The urethrais the canal that carries urine from the bladder out of the body. In men, the prostate gland wraps around the urethra near the bladder.

The reproductive system is the part of the body involved in sexual function. Below are the main parts of the male reproductive anatomy.

1. The urethra transports urine and semen. When you have an orgasm, semen is ejaculated out of the urethra.
2. The testes are glands that produce sperm (reproductive cells) and hormones.
3. The epididymis is a coiled tube that holds sperm while they mature.
4. The vas deferens carry sperm from the epididymis to the penis.

After sexual arousal, sperm move away from the epididymis through the vas deferens. Along the way, the sperm mix with fluids produced by the seminal vesicles and prostate gland to form semen. The semen helps nourish sperm and carry them along.

An erection requires a healthy mind-body “team effort” led by the brain. Upon receiving signals from the brain, the blood vessels, nerves, and hormones work together to cause and maintain an erection.

1.) The Soft (Flaccid) Penis

If nothing is causing a man to become aroused, then his body’s erection “team” of brain, nerves, blood vessels, and hormones won’t begin working to cause an erection. The amount of blood flowing into the penis’s spongy chambers (corpora cavernosa and corpus spongiosum) equals the amount flowing out. His penis remains soft.

2.) The Swollen (Tumescent) Penis

A man becomes aroused through his senses (such as sight or touch) or his thoughts (such as memories or fantasies). During arousal, messages brought by nerves cause the blood vessels and spongy chambers to dilate (open up). More blood flows into his penis than flows out. His penis starts to swell.

3.) The Erect (Rigid) Penis

As arousal continues, nerves keep carrying messages of arousal between the penis and brain. Blood keeps moving into the man’s penis. Blood-swollen tissues press against the veins. Some of the blood is kept from flowing back out. Filled with blood, his penis becomes rigid. The man is able to have intercourse.

The prostate gland is part of the male reproductive system. The prostate is located below the bladder. It surrounds the urethra (the tube that carries urine and semen out of the body). The function of the prostate is to produce a fluid. This fluid mixes with fluid from the seminal vesicles and sperm from the testicles to form semen. During ejaculation, semen travels through the urethra and out of the penis. Prostate health is closely linked to hormones (chemicals that carry messages throughout the body). Normal levels of hormones such as testosterone keep the prostate working correctly.