Adenosine (A) and adenosine diphosphate (ADP) contain different types of bonds in their structures. In adenosine, there is one phosphoester bond. This bond connects the ribose sugar to the phosphate group. In ADP, which has an additional phosphate group compared to adenosine, we find multiple bonds.
ADP contains two types of bonds: it has two phosphoester bonds (one for each of the two phosphate groups linked to the ribose) and one phosphoanhydride bond, which is the bond between the two phosphate groups. The phosphoanhydride bond is crucial for the energy transfer that happens during cellular processes.
Summarizing:
- Adenosine: 1 phosphoester bond
- ADP: 2 phosphoester bonds and 1 phosphoanhydride bond
This distinction helps to understand how energy is stored and released in the form of ATP and ADP during metabolism.