zooplankton

Zooplankton are tiny marine animals that drift with ocean currents and the winds. Many zooplankton can swim up and down the water column, but most are so small that they can't swim strongly against the current. Zooplankton also include larvae, immature forms of larger marine animals. These ocean babies will eventually gain the ability to swim, to propel themselves through water, or settle on the ocean floor when they become adults.

An Underwater Zoo
There are different kinds of zooplankton. The ones that spend their entire lives as plankton are called "holoplankton." (The prefix "holo" means "whole.") Some holoplankton are simple one-celled organisms like ciliates and flagellates. Others are tiny shrimp-like creatures called copepods. Another type of zooplankton, called meroplankton, spends only part of its life as plankton. (The prefix "mero" means "part.") Meroplankton, like crabs, clams, worms, and fish, are babies or young animals that live like plankton until they become adults.

The prefix "zoo" (as in "zooplankton") means:

animal

plant

tiny

Are you right?

Correct!

The prefix "zoo" means "animal" in Greek. Zoology is the study of animals.

Zooplankton are so small, they mainly get around by:

drifting with water currents

moving their back fins

doing the backstroke

Are you right?

Correct!

Some zooplankton have ways of "swimming," but they're so small they still mainly drift with currents.

All zooplankton are made of one cell.

Fact

Fiction

Some zooplankton are simple one-celled animals. Others are tiny, strange-looking shrimp-like creatures.

Description: tiny animals and animal-like organisms
Size: mostly microscopic
Habitat: oceans and freshwater around the world
Diet: phytoplankton (tiny plants) or smaller zooplankton
Characteristics: a variety of sizes, shapes, and colors