This photo was taken by Uwe Kils. It shows an amphipod, a type of plankton. The photo was taken using magnification so users can see the amphipod in detail. In reality, most amphipods are only 1 mm to 140 mm in length.
Click on image for full size
Courtesy of Wikipedia Commons


What is usually small, lives in water and is super important for food chains in lakes and the ocean? It's plankton!

All plankton are drifters. Some can move up and down, but all drift with the water current in the body of water where they live.

Plankton can live in salt water like the ocean and in fresh water.

They can be so tiny that you can't see them with your eye. You'd need a microscope! They can also be bigger like jellyfish, mollusks, and crustaceans. Remember, if it depends on water moving to move side to side, it's plankton!

Plankton are usually divided into three groups - phytoplankton which use photosynthesis to make food, zooplankton which depend on other organisms for food, and bacterioplankton which are the bacteria that drift in open water.

Last modified June 1, 2010 by Lisa Gardiner.

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