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The hydrolysis? of the phosphate-phosphate bonds releases energy that can be used by a variety of enzymes, [motor proteins]?, and [transport proteins]? to carry out the work of the cell. This hydrolysis leads to free inorganic phosphate ion and [adenosine diphosphate]?, which can be broken down further to [adenosine monophosphate]?.
ATP can be produced by various cellular processes, most typically by the oxidation in mitochondria.
In living cells there are also other energetic nucleoside? triphosphates like [guanine triphosphate]?. Energy can be easily transfered between them and ATP in reactions like (catalyzed? by [nucleoside diphosphokinase]?):
See also: cyclic adenosine monophosphate, [adenosine monophosphate]?, [adenosine diphosphate]?