Energy is released to be used by a cell when a phosphate group is removed from adp to form atp added to adp to form atp removed from atp to form adp added to atp to form adp

Removed from atp to form adp

Explanation:

ATP (or adenosine triphosphate) is a molecule capable of storing small amounts of energy (from food breakdown) in its chemical bonds.

When cells need energy to perform various metabolic functions, the ATP molecule breaks down (by hydrolysis).

Then, the bond between the second and third phosphate breaks, releasing energy, leaving one ADP (adenosine diphosphate) molecule and a free phosphate group.

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