Chlamydomonas

Chlamydomonas is a genus of green alga. They are unicellular flagellates. Chlamydomonas is used as a model organism for molecular biology, especially studies of flagellar motility and chloroplast dynamics, biogenesis, and genetics. One of the many striking features of Chlamydomonas is that it contains ion channels that are directly activated by light, such as channelrhodopsin.
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Noun
1. type genus of the Chlamydomonadaceae; solitary doubly-flagellated plant-like algae common in fresh water and damp soil; multiply freely; often a pest around filtration plants
(synonym) genus Chlamydomonas
(hypernym) protoctist genus
(member-holonym) Chlamydomonadaceae, family Chlamydomonadaceae

The unicellular green alga which is probably the closest living organism to the ancestor of green plants. It reproduces bith asexually and sexually (two mating types). When reproduces sexually, the mitochondria are inherited from the the (-) mating type and chloroplasts from the (+) mating type.