Protist

A paramecium, seen at the microscope.

The amoeba is a tiny, one-celled, shape-shifting microorganism.

Protist is a common name given in biology for any eukaryot microorganism, meaning a living being that can't be seen with unaided eye and will need a microscope to be seen, and that is made of cells containing a nucleus.

Eukaryots are a large group of living beings (with the two others being bacteria and archae), recognisable by their cells with nucleus. Some of them, such as animals, plants and fungi, are often quite tall, but others (including some plants and fungi) are so tiny that they will need a microscope to be seen : they are all called protists.

Protists therefore don't make a true group, it is only a practical distinction. Protists include microscopic algae (such as Chlamydomonas, or Volvox), microscopic fungi (the yeasts), and many other strange living beings belonging to different groups.

These groups use to be less commonly known, since you can't see it with unaided eye. The protists contain a formidable biodiversity, including, for example, paramecia, trypanosoma, euglena...

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