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What are Flagellates?
Flagellates are microscopic animals (Protozoas) with cells with one or more whip-like organelles called flagella who live in water. They are named after their means of locomotion in the water.
(Protozoa have traditionally been divided on the basis of their means of locomotion, although this is no longer believed to represent genuine relationships:)
Most protozoans are too small to be seen with the naked eye — most are around 0.01–0.05 mm, although forms up to 0.5 mm are still fairly common — but can easily be found under a microscope.