Sexual love. Conceptual computer artwork of two sperm cells (spermatazoa) forming the shape of a heart. This could represent concepts relating to love and sexual reproduction. Sperm cells are the male reproductive cells. The heads of the sperm cells (bottom, red) contain the genetic material. During intercourse, millions of sperm cells are deposited in the female reproductive tract. They use their tails to move towards the egg cell (female reproductive cell), where they will attempt to fertilise it. Only one sperm cell will succeed in fertilising the egg.