sperm

sperm The male sex cell (gamete). The sperm has an oval head that contains its genetic matter, and it is propelled by a flagellating tail. A sperm is carried into the female reproductive tract within the semen (ejaculate). If the sperm is able to travel up into a fallopian tube, it must then break through the cell wall of the egg (the female gamete, or ovum) to fertilize the egg and form a zygote. This formation process is called fertilization. See also fertilization; ovulation; ovum.