Why is ATP so important to living organisms?

Question

Why is ATP so important to living organisms?

Answer 1

Energy is stored in the bond created when making ATP from ADP.  ATP is an easy way to store energy, as this bond can be broken, allowing this energy to be used later.

Answer 2

ATP is the primary source of free energy in all living cells. ATP provides the energy for muscles to contract, nerves to conduct impulses, and all that cells require to build protein, pump in substances they need, permit enzymes to act, and so on. All living organisms require ATP.