What is the definition of energy in biological terms?

Energy in biological terms is defined as the capacity to do work. This concept is central to understanding how organisms function and survive. In biological systems, energy is crucial for various processes, including metabolism, growth, reproduction, and maintenance of homeostasis.

For instance, cells utilize energy to transport molecules across membranes, synthesize new compounds, and perform mechanical work such as muscle contraction. The energy that fuels these activities often comes from the breakdown of molecules like glucose during cellular respiration, where the stored chemical energy is converted into forms that cells can use, such as ATP (adenosine triphosphate).

This definition emphasizes that energy is not merely about the presence of substances but about the potential to effect change and perform tasks, aligning with the dynamics of living organisms that continuously interact with their environment to sustain life processes.