Human sperm. Light microscopy footage of healthy human sperm cells. Sperm cells are the male reproductive cells, and contain male genetic information, as half of a man's chromosomes. Each sperm cell has a long tail, which beats to propel it to meet a female egg cell. Fusion of the sperm and egg is called fertilisation, and produces a cell with a full set of chromosomes, half from the father and half from the mother. A human sperm cell has a head some 5x3 micrometres in size, and a 50-micrometre-long tail.