Components of ATP
Adenosine triphosphate (ATP) is a nucleotide derivative. Each ATP molecule contains:
- adenine, a nitrogen-containing base
- ribose, a pentose sugar
- three phosphate groups
Adenine bonded to ribose forms adenosine. Phosphate groups can then be attached to this adenosine component.
adenine + ribose = adenosine
AMP, ADP and ATP
Adenosine can have one, two or three phosphate groups attached. The prefixes mono-, di- and tri- indicate these different numbers.
| Abbreviation | Full name | Phosphate groups |
|---|---|---|
| AMP | Adenosine monophosphate | 1 |
| ADP | Adenosine diphosphate | 2 |
| ATP | Adenosine triphosphate | 3 |
Exam Tip: If asked to describe ATP's structure, identify adenine, ribose and three phosphate groups. Keep adenine and adenosine distinct: adenosine consists of adenine joined to ribose.