Sea anemones, like corals, belong to the Class Anthozoa. Within the Class Anthozoa, sea anemones are classified in the Order Actiniaria. Sea anemones remain polyps for their entire adult life, they never transform into the medusa form as jellyfish do.
Sea anemones are capable of sexual reproduction, though some species are hemaphroditic (a single individual has both male and female reproductive organs) while other species have individuals of separate sexes. Egg and sperm are released into the water and the resulting fertilized eggs develop into a planulae larva which attaches themselves to a solid surface and develop into a polyp. Sea anemones can also reproduce asexually by budding new polyps from existing ones.
Sea anemones are, for the most part, sessile creatures which means they remain attached to one spot. But if conditions grow inhospitable, sea anemones can detach from their home and swim off in search of a more suitable location. They can also slowly glide on their pedal disc and can even crawl on their side or by using their tentacles.