Sperm
A sperm or spermatozoon or spermatozoid is a form of gamet (germ cell), a male germ cell capable of independent movement, which serves to fertilise the female germ cell, the egg cell.
Sperms are usually produced by an individual in large numbers and are considerably smaller than the egg to be fertilised because, unlike the egg, they do not contain large plasma amounts and yolk-containing nutrients.
The testicular tubules consist of a connective tissue shell and the germ epithelium. The germ epithelium consists of the germ cells or their precursors and the Sertoli supporting cells. The Sertoli cells form the epithelium of the seminal tubules. They form numerous cell processes. The cell processes of neighboring Sertoli cells are connected to each other near the basement membrane via tight junctions and thus form the so-called blood-testicles barrier. The male germ cells are located in the invaginations of the plasma membrane at different degrees of maturity.