The testicles

The testicles

• Testicles are small and oval-shaped. They hang below your penis in a sac called the scrotum.
• The testicles produce sperm from puberty (around 13-14 years old) onwards. When sperm meet with a female egg during sex, this can result in a pregnancy.
• The testicles make millions of sperm a day, but if sperm aren't ejaculated (spurted out from the end of the penis), then they're reabsorbed back into your body. This means that you don't get a build up of sperm.
• Sperm stay in the testicle until they get ejaculated through the end of the penis. Sperm travel from the testicle, through a tube called the epididymis, then into the spermatic cord, then the ejaculatory duct, before going through the urethra (this is the same tube you pee from). You can see all these body parts in the diagram below.  
• From puberty, your testicles produce a hormone called testosterone. This gives you a lower voice, hair on your face and body, and makes your muscles get bigger. You also need it for your sex drive and for getting an erection.

The testicles and their surrounding structures
View a large version of the diagram of the testicles and surrounding structures|

Lymph nodes (glands)

Sometimes cancer cells from the testicle can spread to lymph nodes at the back of the tummy (abdomen). Lymph nodes are small and round (like a bean), and connect to each other by tiny tubes that carry fluid called lymph. We have groups of lymph nodes throughout our bodies and they’re part of the lymphatic system, which protects us from infections and diseases.  

Lymph from the testicles travels along these tubes to the lymph nodes in the tummy. This is why they're a common place for the cancer cells to spread to. You’ll have a scan to check your lymph nodes.