The five-kingdom classification system divides life into five groups based on cellular structure, nutrition, and reproduction. The five kingdoms are: Monera: Unicellular organisms, prokaryotic, including bacteria; Protista: Unicellular or simple multicellular eukaryotic organisms, such as protozoa and algae; Fungi: Eukaryotic organisms, non-photosynthetic, absorb nutrients from other organic matter (e.g., mushrooms, molds); Plantae: Multicellular, photosynthetic eukaryotes that produce their own food (e.g., plants); Animalia: Multicellular, eukaryotic organisms that are heterotrophic and usually capable of movement (e.g., animals).