Question

why does ATP contains a large amount of energy?

Answer 1

By the cell maintaining ATP at high concentrations and ADP and AMP at low concentrations the energy released from breaking ATP down to ADP or AMP is much larger than if there were equal amounts of ATP, ADP and AMP. This is why ATP is said to contain energy, like pushing a bowling ball to the top of a hill and then letting it roll down ATP releases energy when it is turned into its products.