carbon cycle: the continuous process by which carbon is exchanged between organisms and the environment
photosynthesis: the process by which green plants, algae and certain kinds of bacteria make food from carbon dioxide and water, using chlorophyll, a cellular structure, and the energy from sunlight
respiration: the process in which organisms exchange gases, especially oxygen and carbon dioxide, with the environment; respiration in green plants occurs during photosynthesis
sedimentary rock: rocks formed when sediment, such as sand or mud, is deposited and becomes tightly compacted; examples of sedimentary rock include sandstone and limestone