The Kingdom Protista contains the protozoa, algae, slime molds, and water molds. All of these organisms are eukaryotic and lack tissue differentiation. These single-celled microorganisms are noted for their ability to move independently.
Protozoans live in environments that vary from soil to the bodies of other organisms.
Many species make up zooplankton , one of the primary sources of energy in aquatic ecosystems. Algae These plant-like protists all carry on photosynthesis. Although most algae are single-cell organisms, some are large multicellular organisms. The largest algae are the seaweeds known as kelp that are hundreds of feet long. All algae, no matter their size, lack tissue differentiation.