: The internal regulation of a system to maintain a constant, stable state, such as body temperature control.

: Physical displacement, either of the entire organism or of structures within its cells.

: The process by which organisms produce new individual offspring.

: The chemical transformation of energy. It includes anabolism (building up cellular components) and catabolism (breaking down organic matter).

Scientists often categorize these vital actions into several "life processes" that distinguish living things from non-living matter:

: The ability to react to external environment changes, such as a plant turning toward the sun.