Tetrahymena

Tetrahymena is a genus of free-living freshwater ciliates found in ponds and lakes worldwide, covered in rows of beating cilia that propel it through the water as it feeds on bacteria and other microorganisms. It has become one of the most important model organisms in cell biology, used in research that helped establish the existence of telomerase, the enzyme that maintains chromosome ends, work that contributed to a Nobel Prize, and its ease of laboratory culture has made it a standard tool for studying basic cellular processes shared across eukaryotic life.