Environmental Systems and Societies (ESS) Topic 1 Foundations Practice Test

The key idea is that systems have places where quantities accumulate, called stores or storage. Storage describes the stock that is held within the system at any given time, highlighting the act of keeping or accumulating matter or energy. A sink, in contrast, usually refers to a process or location where material is removed from the system rather than simply held. A reservoir can be another term for a store, but storage is the precise label for the place where the quantity is held inside the system. So, storage best describes the function of holding matter or energy within the system.