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What type of symmetry do sponges have? A: Some sponges have radial symmetry, but many species are irregular in shape and have no symmetry at all. Two simpler groups of sponges, known as asconoid an... Full Answer >
A sponge is covered with tiny pores, called ostia, which lead internally to a system of canals and eventually out to one or more larger holes, called oscula. Within the canals of the sponge, chambers are lined with specialized cells called choanocytes, or collar cells.