<P> Cyanobacteria / saɪˌænoʊbækˈtɪəriə / , also known as Cyanophyta , is 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 ( kyanós ) = 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> Cyanobacteria / saɪˌænoʊbækˈtɪəriə / , also known as Cyanophyta , is 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 ( kyanós ) = 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>
where do blue-green algae get their energy from
where do blue-green algae get their energy from
photosynthesis
photosynthesis