Caring for the Oceans Plankton are simple forms of plants that are the major source of food for ocean animals. Like other plants, plankton feed themselves through the process of photosynthesis. Fueled by the energy of sunlight, they use chlorophyll to convert carbon dioxide and water into a simple, sugary food. In plankton and other marine life, chlorophyll gives off a natural glow during photosynthesis.
Plankton is the bottom of the food chain in the ocean.
They are eaten by tiny marine animals, who in turn are eaten by other animals. Like other plants, plankton gives off oxygen as a byproduct of photosynthesis. Much of the world s oxygen comes from plankton. So, it is important for the whole world that we take care of our oceans. One of the ways scientists check the health of the oceans is to measure the amount of plankton in a given area.