Sponges are capable of both asexual and sexual reproduction. These parazoans reproduce most commonly by sexual reproduction and most are hermaphrodites, that is, the same sponge is capable of producing both male and female gametes. Typically only one type of gamete (sperm or egg) is produced per spawn. Fertilization occurs as sperm cells from one sponge are released through the osculum and carried by water current to another sponge.