<Li> Cyanophyta Steinecke, 1931 </Li> <Li> Oxyphotobacteria Gibbons & Murray, 1978 </Li> <P> Cyanobacteria / saɪˌænoʊbækˈtɪəriə /, also known as Cyanophyta, are a phylum of bacteria that obtain their energy through photosynthesis, and are the only photosynthetic prokaryotes able to produce oxygen . The name "cyanobacteria" comes from the color of the bacteria (Greek: κυανός, translit . kyanós, lit .' blue'). Cyanobacteria (which are prokaryotes) used to be called "blue - green algae". They have been renamed' cyanobacteria' in order to avoid the term "algae", which in modern usage is restricted to eukaryotes . </P> <P> Unlike heterotrophic prokaryotes, cyanobacteria have internal membranes . They are flattened sacs called thylakoids where photosynthesis is performed . </P>

Cyanobacteria (blue-green algae) is an example of what type of plankton
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