A sperm cell, or spermatozoon (pl.spermatozoa) (in Greek: sperm = semen and zoon = alive), is the haploid cell that is the male gamete. It is carried in fluid called semen, and is capable of fertilising an egg cell to form a zygote. A zygote can grow into a new organism, such as a human. Sperm cells contain half of the genetic information needed to create life. Generally, the sex of the offspring is determined by the sperm, through the chromosomal pair "XX" (for a female) or "XY" (for a male). Sperm cells were first observed by Antoni van Leeuwenhoek in 1679.
Sperm structure and size
Individual spermatozoa are highly differentiated cells, composed normally of a head, basal body (or midpiece), and tail. The head contains some cytoplasm and the nuclear material for fertilization. The basal body contains a large concentration of mitochondria that provide the energy for sperm motility through the production of ATP. The spermatozoan tail is typically a flagellum used for propulsion.
In humans, sperm cells consists of a head 5 µm by 3 µm and a tail 50 µm long. The tail flagellates, which propels the sperm cell. The cell is characterized by a minimum of cytoplasm.
Sperm are produced in the seminiferous tubules of the testes in a process called spermatogenesis. Round cells called spermatogonia divide and differentiate eventually to become sperm. During sexual intercourse the sperm is deposited in the vagina - and then it moves to the ovum.
External link
The Handbook of Andrology (http://www.andrologysociety.com/resources/handbook.asp)
(1977) observed acrosome malformations of spermatids and spermatozoa in the testes of 2 infertile males who were investigated by light and electron microscopy.
Defective differentiation of the acrosome granule in spermatids appeared to be responsible for the malformation of mature spermatozoa.
In Friesian bulls, a characteristic defect of the acrosome ('knobbed' spermatozoa) associated with sterility appears to be autosomal recessive.
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