Homeostasis – The property of either an open system or a closed system, especially a living organism, that regulates its internal environment so as to maintain a stable, constant condition. Life – A condition of growth through metabolism, reproduction, and the power of adaptation to environment through changes originating internally. Microscopic – The scale of objects, like cells, that are too small to be seen easily by the naked eye and which require a lens or microscope to see them clearly.