定義： A state of the cingulum wherein the end of the cingulum is lower than the beginning. Facing the ventral side of the cell, the cingulum on your right-hand side is higher than the cingulum on your left-hand side.
定義： Living in the fluid medium (water or air) but unable to maintain their position or distribution independently of the movement of the water/air mass (adapted from Lincoln et al., 1998).
定義： An aquatic biome that comprises systems of open-ocean and unprotected coastal habitats, characterized by exposure to wave action, tidal fluctuation, and ocean currents as well as systems that largely resemble these. Water in the marine biome is generally within the salinity range of seawater: 30 to 38 ppt.
