The semen is the ejaculate fluid produced by and released from the male reproductive organ. It is slimy and whitish in colour. It may contain the sperm cells together with the secretions from the sexual gland.
In humans, the semen contains various enzymes and fructose apart from the sperm cells. These elements promote the survival of the sperm cells as well as to provide medium for them to swim. The process that results in the release of semen is termed ejaculation. As the sperm cells pass through the ejaculatory ducts they become mixed with fluids mainly from seminal vesicles, prostate, and bulbourethral glands. The typical components of semen are as follows: spermatozoa (2-5%) produced and released from the testes, seminal vesicle secretions (65-75%, i.e. comprised of amino acids, citrate, flavins, fructose, and certain enzymes), prostate secretions (25-30%, i.e. comprised of acid phosphatase, citric acid, fibrinolysin, proteolytic enzymes, zinc, etc.), and bulbourethral gland secretions (<1%, i.e. contains galactose and mucus).
Word origin: Latin sēmen (“seed”)
- seminal fluid