Term | Definition |
Osculum | a large opening on a sponge through which filtered water is expelled |
Amoebocytes | cells within a sponge that produce its skeletal structure, perform digestion, and repair cell damage |
Gemmule | a group of cells surrounded by a shell made of spicules |
Metamorphosis | a complete morphological change from larval to adult form |
Spherical Symmetry | a body form in which any cut through the organism's center results in identical halves |
Radial Symmetry | a body form in which any longitudinal cut (along the length) through the organism's central axis results in identical halves |
Bilateral Symmetry | a body form in which only one longitudinal cut through the organism's center results in identical halves |
Polyp | an attached cnidarian stage, appearing sac-like or barrel-like |
Medusa | a free-swimming cnidarian stage, appearing bell-like or umbrella-like |
Mesoglea | a jelly-like substance between the inner layer and outer layer of cells in a cnidarian |
Dorsal | referring to the top (or back) surface of an animal |
Ventral | referring to the bottom (or belly) surface of an animal |
Mutualism | a relationship between two or more organisms of different species where both benefit from the association |
Commensalism | a relationship between two or more organisms of different species where one benefits and the other is neither harmed nor benefited |
Parasitism | a relationship between two or more organisms of different species where one benefits and the other is harmed |
Coelom | a body cavity within organisms containing specialized tissue |
Gills | extensions of the body containing thin-walled blood vessels that allow for easy absorption of oxygen from the outside surface |