Bacteria are classified into 5 groups according to their basic shapes: spherical (cocci), rod (bacilli), spiral (spirilla), comma (vibrios) or corkscrew (spirochaetes). They can exist as single cells, in pairs, chains or clusters.
Explanation:
you must add activation energy to initially break the chemical bonds. Catalysts simply lower the activation energy needed to do the chemical reaction going. reactions to occur without themselves being used up in the reaction. Energy is usually needed to break the bonds and get the reaction going.
ecosystem:
Living and Nonliving Things in the Ecosystem. Ecosystems -- biological communities -- include living organisms like animals, plants, insects and bacteria, as well as nonliving components like rocks, soil, water and sunlight.
