How is energy released from molecules to power cellular functions?

Question

1. An ATP molecule adds a phosphate group, forming ADP.
2. An ATP molecule releases a phosphate group, forming ADP.
3. An ADP molecule releases a phosphate group, forming ATP.
4. An ADP molecule adds a phosphate group, forming ATP.

Answer 1

The correct statement is:

2. An ATP molecule releases a phosphate group, forming ADP.

In biological systems, the energy stored in adenosine triphosphate (ATP) is released when ATP undergoes hydrolysis, breaking one of its high-energy phosphate bonds. This reaction converts ATP into adenosine diphosphate (ADP) and inorganic phosphate (Pi), and releases energy that is utilized to power various cellular functions, such as muscle contraction, active transport, and biosynthesis of molecules.