B0007640 ATP
Credit: Anna Tanczos. Wellcome Images
Molecular model showing the structure of adenosine triphosphate (ATP). ATP is the unit of energy for all living things. The molecule is composed of three parts: a sugar ribose molecule (red and white), a base molecule made up of carbon and nitrogen atoms (grey and purple) and lastly a string of phosphate atoms (orange).

It is these phosphate groups that is key to the function of ATP. When energy is required, ATP is involved in an enzymatic reaction, which results in the loss of a phosphate group and a release of energy to form adenosine diphosphate (ADP). During resting state, when energy is not required the reverse reaction takes place to reform ATP from ADP.
Digital artwork/Computer graphic
2010 Published: –

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