Semen is also known as seminal fluid. Semen is the organic fluid ejaculated from the male reproductive tract which contains sperm cells. Semen also contains liquid to form a seminal plasma that helps to keep sperm viable. Semen is generally made from combining different fluids having amino acids, citrate, enzymes, fructose, galactose, acid phosphate, mucus and spermatozoa. In an adult male, spermatozoa are produced by testes that contribute only ten percent of the total semen.