A large variety of creatures live on the continental shelves which are covered with ocean water. The most numerous are the floating plankton. Zooplankton are microscopic animals, while phytoplankton are microscopic plants. Phytoplankton contain chloroplasts and live near the surface of the ocean in order to receive green enough light to synthesize their own food from carbon dioxide(co2) and water. zooplankton have no green chloroplasts, cannot make their own food, and must eat phytoplankton. Fish and other sea animals constantly supply carbon dioxide to the water which the phytoplankton must have to synthesize food. The nekton eat the plankton and other ne whereas the benthos crawl on the sea floor, eating waste materials and dead plants and animals that have sunk to the bottom.