ADP (Adenosine diphosphate) is formed when ATP (Adenosine triphosphate) loses one of its phosphate groups. Essentially, it's the result of ATP being used for energy.
Here's a breakdown:
The ATP to ADP Conversion
When a cell requires energy to perform a task, ATP undergoes a process called hydrolysis. This process involves:
- Splitting a Phosphate: The ATP molecule breaks off one of its three phosphate groups.
- Formation of ADP: This action converts ATP into ADP (Adenosine diphosphate) and an inorganic phosphate (Pi). The reaction can be represented as: ATP → ADP + Pi.
- Energy Release: The chemical bond holding that phosphate molecule contains energy. When the bond is broken, this energy is released and becomes available to power cellular work. As stated in the reference, "If a cell needs to spend energy to accomplish a task, the ATP molecule splits off one of its three phosphates, becoming ADP (Adenosine di-phosphate) + phosphate. The energy holding that phosphate molecule is now released and available to do work for the cell."
Summary Table: ATP to ADP
| Feature | ATP (Adenosine Triphosphate) | ADP (Adenosine Diphosphate) |
|---|---|---|
| Phosphate Groups | Three | Two |
| Energy Content | High | Lower |
| Formation | Formed by adding a phosphate group to ADP. | Formed by removing a phosphate group from ATP. |
