The term mixotrophic can describe organisms (usually algae or bacteria) capable of deriving metabolic energy both from photosynthesis and from external energy sources. These organisms may use light as an energy source, or may take up organic or inorganic compounds. They may take up simple compounds osmotically (by osmotrophy) or by engulfing particles (by phagocytosis or myzocytosis). A seaweed (Laurencia) up close: the branches are multicellular and only about 1 mm thick. ... Phyla/Divisions Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Omnibacteria Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular, bacterium) are a major group of living organisms. ... Leaf. ... Phagocytosis (literally, cell eating) is a form of endocytosis where large particles are enveloped by the cell membrane of a (usually larger) cell and internalized to form a phagosome, or food vacuole. ...