colloid. 1  a solid, liquid, or gaseous substance made up of very small, insoluble particles (as single large molecules or masses of smaller molecules) that remain in suspension in a surrounding solid, liquid, or gaseous medium of different matter.
Nekton. Nekton are the animals that can move by themselves in the ocean waters. Nekton live in all zones of the ocean. However, just like benthos and plankton, most live in the sunlight zone or shallow twilight zone since there is the most sunlight and it is easy to feed on smaller organisms such as krill and minnows.
Plankton is the foundation of the ocean food web. The word plankton comes from the Greek word  planktos  which means drifting. Zooplankton are ocean animals that don't swim at all or are very weak swimmers, and they drift or move with ocean currents. They can be found in the sunlit zone and in deep ocean waters. Zooplankton range in size from tiny microbes to jellyfish, although most zooplankton are tiny, single-celled organisms. There are two types of zooplankton.