Operational definition

Allocation function.

The continuing expenditure of energy and matter required to preserve the existing organized, viable state of a biological system without counting net growth or reproductive production.

It includes:

Maintenance is a rate of sustaining existing organization, not merely inactivity.

46.1 Basal cellular maintenance

46.2 Organ-system maintenance

46.3 Thermoregulation

Thermoregulation applies where biologically relevant; it is not a universal cost of equal importance across life.