Human Balls: Anatomy, Function, and Health of the Testes
Gain a clear understanding of the testicles, from their complex internal workings to their vital role in overall male health and well-being.
The testicles, or testes, are sophisticated organs within the male reproductive system. They are responsible for both reproduction and regulating the hormones that influence male development and characteristics. This overview covers their physical structure, primary roles, common health issues, and methods for maintaining testicular health.
The Anatomy of Human Testicles
The testes are housed within the scrotum, a sac of skin hanging outside the abdominal cavity. The scrotum functions as a climate control system, contracting to bring the testes closer to the body for warmth or relaxing to let them cool down. This maintains a temperature slightly lower than the body’s core, which is necessary for producing viable sperm.
Each testis is an oval-shaped gland encased in a tough, fibrous capsule called the tunica albuginea. This outer layer extends inward, dividing the internal space into 200 to 300 compartments known as lobules. This structure provides a protected and organized environment for the delicate components within.
Inside these lobules are hundreds of coiled tubes called seminiferous tubules, the production sites for sperm. The tubules are lined with Sertoli cells, which provide nutritional support to developing sperm, and the germ cells that become sperm. Situated in the tissue between these tubules are Leydig cells, which produce testosterone.
Once produced, sperm move from the seminiferous tubules into the epididymis, a long, coiled tube that sits on the back of each testicle. It is within the epididymis that sperm mature and are stored before being transported away by a tube known as the vas deferens.
Primary Functions: Producing Sperm and Hormones
The primary function of the testes is spermatogenesis, the process of producing sperm. This process begins at puberty and continues throughout a man’s life. Within the seminiferous tubules, germ cells undergo a series of divisions, a journey that takes approximately 64 to 72 days to complete.
After their initial formation, immature sperm are not yet capable of fertilization. They travel to the epididymis for a maturation period that lasts several weeks. Here, they acquire motility (the ability to swim) and the capacity to fertilize an egg, and are stored until ejaculation.
Parallel to sperm production, the testes have an endocrine function. The Leydig cells, located between the seminiferous tubules, produce testosterone, the principal male sex hormone. This hormone is released directly into the bloodstream.
Testosterone is responsible for developing male reproductive tissues like the testes and prostate. It also drives secondary sexual characteristics during puberty, including facial hair growth, increased muscle mass, and a deepening voice. Throughout life, testosterone also influences libido, mood, and energy levels.
Understanding Common Testicular Health Issues
Testicular torsion is a medical emergency that occurs when a testicle rotates, twisting the spermatic cord that brings blood to it. This cuts off the blood supply, causing sudden and severe pain, swelling, and sometimes abdominal pain. Immediate surgery is required to prevent permanent damage to the testicle.
A varicocele is the enlargement of veins within the scrotum, similar to a varicose vein. Often described as feeling like a “bag of worms,” it may cause a dull ache or heaviness, particularly after standing for long periods. While many are harmless, they can sometimes affect fertility or cause the testicle to shrink.
Epididymitis (inflammation of the epididymis) and orchitis (inflammation of the testicle) are often caused by bacterial infections, including STIs, or viruses like mumps. Symptoms include pain and swelling of the scrotum, which may develop over several days, along with fever and a feeling of heaviness.
Testicular cancer, while relatively rare, is the most common cancer in men between 15 and 35. It usually presents as a painless lump or swelling, a change in the size or shape of a testicle, or a dull ache in the lower abdomen or groin. When detected early, the prognosis is very positive.
Maintaining Good Testicular Health
A monthly testicular self-exam (TSE) helps you learn what is normal for your body, making it easier to detect changes early. The best time for an exam is during or after a warm shower or bath, when the scrotal skin is relaxed.
To perform a self-exam, check one testicle at a time by gently rolling it between the thumb and fingers. Feel for any hard lumps or changes in the size, shape, or consistency. The testicles should feel smooth and firm, and it is normal for one to be slightly larger or hang lower than the other.
In addition to self-exams, protective measures can reduce injury risk. Wearing an athletic supporter during contact sports helps prevent trauma. It is also advisable to avoid prolonged exposure to high temperatures from hot tubs or laptops on your lap, as excess heat can negatively impact sperm production.
A healthy lifestyle contributes to reproductive health. This includes a balanced diet, regular physical activity, and avoiding smoking and excessive alcohol consumption. If you discover any lumps, swelling, pain, or other changes during a self-exam, consult a healthcare professional without delay.