how and where are sperm and semen formed in the male reproductive system?

Answer 1

Semen is a white or grey liquid, emitted from the urethra (tube in the penis) on ejaculation. Semen consists of the secretions of several glands but only 5 per cent comes from the testicles.

The spermatozoa take over 70 days to develop and are produced in the testicles. Individual sperm develop within the testicles from a cell called a spermatogonium. The spermatogonium divides to produce spermatocytes, which then develop into spermatids. The spermatid develops into a mature spermatozoan. This process takes about 60 days and the sperm then takes a further 10 to 14 days to pass through the ducts of each testicle and its sperm-maturing tube, the epididymis, before it can leave the body in the semen, during ejaculation. The fluid produced by the testicles contains several chemicals, but is particularly rich in testosterone.

The seminal vesicles usually contribute more than half of the seminal volume. Their secretions are particularly rich in a sugar called fructose, which is an essential nutrient for the spermatozoa.