Bioenergetically:
coordinated homeostatic energy transduction ceases
Consequences include collapse of:
- membrane potentials
- ion gradients
- controlled redox states
- active transport
- molecular turnover
- organized repair
Operational definition
Terminal state transition.
The irreversible loss, at the defined biological level, of the integrated capacity to maintain or resume self-sustaining organization and homeostasis.
The system boundary must be specified:
- a cell may die while the organism survives;
- part of a colony may die while the colony persists;
- tissues may remain metabolically active briefly after organismal death.
Loss of membrane gradients and ATP is commonly a consequence of death, but no single molecular event defines every kind of biological death.