title: Free oxygen and evolutionary progress.
mesh_terms: D000332:Aerobiosis; D001419:Bacteria / Q000378:metabolism; D005075:Biological Evolution; D002374:Catalase / Q000378:metabolism; D000458:Cyanobacteria / Q000378:metabolism; D004463:Ecology; D008928:Mitochondria / Q000378:metabolism; D010101:Oxygen Consumption; D010788:Photosynthesis
chemical_list: D002374:Catalase