Penis and Testicles

The penis has two main jobs: it helps with urination (letting urine leave the body) and ejaculation (releasing semen). During urination, the penis acts as a passage for urine. During ejaculation, it releases semen, which carries sperm.

The testicles, found inside the scrotum, are very important for male health. They make and store sperm, which is needed to help create a baby. They also produce testosterone, a hormone that affects male growth, development, and fertility.

The penis and testicles work together to support key body functions like removing waste and reproduction.

Male Reproductive Anatomy

What Do the Penis and Testicles Do?

The penis and testicles are like a team, each with their own important jobs:

  • The Penis: It has two main roles. First, it helps with urination by carrying urine out of the body. Second, it delivers semen (which contains sperm) during ejaculation.

  • The Testicles: These are like factories. They produce and store sperm, and they also make testosterone—the hormone that helps with growth, fertility, and other male characteristics.

What’s on the Outside?

The penis and scrotum make up the visible parts of the male reproductive system:

  • Penis: The penis has two main parts: the shaft and the glans (the head). Separating the shaft from the glans is a ridge called the corona. At birth, most penises are covered by a foreskin, a loose piece of skin that can be pulled back to expose the glans. On the underside of the penis is the frenulum, a small band of tissue connecting the foreskin to the glans.

  • Scrotum: This is the sac that hangs below the penis and holds the testicles. It’s more than just a pouch—it keeps the testicles at the perfect temperature. When it’s cold, a muscle called the cremaster pulls the scrotum closer to the body for warmth. When it’s warm, the scrotum relaxes, letting the testicles hang lower to stay cool.

What’s on the Inside?

Behind the scenes, the internal parts do a lot of the heavy lifting:

  • Urethra: This is a tube that runs through the penis, carrying both urine and semen (but never at the same time).

  • Epididymis: A coiled tube on the back of each testicle where sperm matures before it’s ready to go.

  • Vas Deferens: These long tubes carry sperm from the epididymis to the seminal vesicles when it’s time for ejaculation.

  • Seminal Vesicles: These small glands make most of the fluid in semen, giving sperm the energy to swim.

  • Prostate Gland: About the size of a walnut, the prostate adds a special fluid to semen that helps sperm move and survive. Some people find this area sensitive to touch.

  • Cowper’s Glands: Also called bulbourethral glands, these produce a fluid known as pre-ejaculate (precum), which helps prepare the urethra for semen.

What Happens When You’re Aroused?

Erections

An erection happens when the spongy tissue in the penis fills with blood, making it firm. This can occur when you’re aroused by thoughts, physical touch, or stimulation of sensitive areas called erogenous zones (like the penis, scrotum, or even nipples).

Ejaculation

Ejaculation is when semen leaves the body through the urethra, usually during orgasm. This can happen during sex, masturbation, or even in your sleep (known as a wet dream). It’s a natural process, especially during puberty. Ejaculation is also how sperm reaches an egg during conception, so using contraception like condoms is important to prevent pregnancy and protect against STIs.

Taking Care of Your Penis and Testicles

Keep It Clean

Wash your penis and testicles daily with warm water. If you have a foreskin, gently pull it back to clean underneath. This helps prevent a substance called smegma from building up, which can cause irritation or smell bad if not cleaned away.

Grooming

Pubic hair is completely natural and helps protect your body. Some people like to groom or remove it, while others leave it as it is. If you choose to trim or shave, be careful and use clean tools to avoid irritation or injury. Always moisturize afterward to keep the skin calm.

Check Yourself

Get to know how your testicles feel so you can notice if something changes. The best time to check is during a shower when the skin is relaxed. Gently roll each testicle between your fingers and thumb to feel for any lumps, swelling, or changes.

When to See a Doctor

If you notice discomfort, pain, unusual discharge, or changes in smell, it’s a good idea to talk to a healthcare provider. Similarly, if you find lumps or experience persistent aches, don’t hesitate to get checked. Testicular cancer is rare but is more common in younger men, so regular self-checks are a great habit to start.

Taking care of your reproductive health is easy when you build simple routines like cleaning, self-checks, and using protection during sex. If you ever have questions or concerns, healthcare providers are there to help.