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an opening in a sponge's body through which water exits
one of the small openings in a sponge's body through which water enters
any of the flagellate cells that line the cavities
an asexual reproductive structure produced by some freshwater sponges
within the body wall of a sponge, a specialized cell that crawls about and delivers nutrients from the choanocytes to the rest of the body cells
a needle of silica or calcuim carbonate in the skeleton of some sponges
a fibrous protein that contains sulfur and composes the fibers of the skeleton of some sponges
an independent and immature form of an organism that is morphologically different from the adult form
an organism that obtains organic food molecules by eating other organisms or their byproducts and that cannot synthesize organic compounds from inorganic materials
the outer surface layer of cells of a plant or animal