Phytoplankton are small, single-cell plants that usually live in the sunny upper layers of fresh water bodies and the ocean. The name comes from the Greek words phyton (plant) and planktos (wanderer or drifter). Phytoplankton help make planet Earth habitable by producing about half of the oxygen made by all plant life on Earth.
Just like plants on land, phytoplankton use the energy from the sun to create energy in a process called photosynthesis. Chlorophyll is the molecule that captures the energy to change carbon dioxide and water into sugar. The plants consume carbon dioxide and release oxygen.
Phytoplankton are too small to be seen with the unaided eye, but when they are present in high numbers, they may color the water in blues and greens because of the chlorophyll in their cells. Because phytoplankon are at the bottom of the ocean food chain, they help sustain almost all ocean life. They are fed upon by other organisms such as zooplankton. There are some 10,000 species of plankton.Back to NASA VizApps