The Sperm cell is known as the male reproductive cell. The word sperm comes form the Greek word for seed, 'sperma'. Sperm cells contain 23 chromosomes and are known as haploid cells, since they contain half of its parents' chromosomes. The spermatozoa of animals are produced in the gonads via meiotic division during spermatogenesis. The Sperm cell consists of two structures: the head which is 5 µm long and 3 µm wide and a flagellum that is 50 µm long. The structure was first observed in 1677 under a microscope.
It can be either motile or non-motile. It is considered motile (or "spermatozoon") when the sperm has the single flagellum, which moves in a whip-like manner and it goes to the egg. While the non motile sperm do not have the flagellum and it is called "spermatium".
- ↑ News Medical Life Sciences. Sperm - Male Reproductive Cells. Dr Ananya Mandal. September 2014. Available from: http://www.news-medical.net/health/What-is-Sperm.aspx