Life Without These Body Fluids Is Impossible

Semen
Semen, the fluid released by males at ejaculation, generally contains spermatozoa, the gametes that fertilize the female egg, though this is not the case for males who have undergone the most common sterilization procedure, vasectomy.In addition to providing a medium through which sperm can “swim,” semen also contains fructose, a sugar that nourishes the sperm, as well as alkaline secretions that help to neutralize the normally acidic environment of the vagina.Females are born with all the eggs they will ever have, but males continuously produce gametes from puberty onward, and the average healthy male’s ejaculate of about five milliliters contains approximately 300 million spermatozoa.Why such large quantities are produced when only one sperm can fertilize an egg is a bit of a puzzle, but one explanation may be that the competition between sperm helps to select for the fittest.