Their role is as a scavenger.
Protozoans that Move with Cilia. These protozoans are called Ciliates and have hundreds of tiny cilia which beat in unison to propel them through the water. ... In addition to locomotion, the Paramecium and other ciliates like the Stentor use cilia to sweep food down into their central channel or gullet.
Nitrogen and Oxygen make up the greatest percentage of the atmosphere.
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