1. ATP

2. What is ATP? Adenosine triphosphate (ATP) Supplies energy to the cell
One molecule of ATP is composed of three parts:
Nitrogenous base (adenosine)
Sugar (ribose)
Three phosphate groups
These three phosphate groups are bonded together by high energy bonds

3. Breaking bonds in ATP
Cells break the bonds between the three phosphates to supply energy for most cellular functions
When the bond breaks holding the phosphate, ATP is turned into ADP with a phosphate available for reuse

4. Use and Release of energy
When any of the phosphate bonds are broken or formed, energy is involved
Energy is released when a phosphate is removed from ATP
Energy is used when phosphate is attached to the molecule
To constantly supply the cell with energy, the ADP is recycled creating more ATP which carries much more energy than ADP

5. ATP – ADP cycle
To supply cells with energy, a “high energy” bond in ATP is broken. ADP is formed and a phosphate is released back into the cytoplasm
ATP  ADP + phosphate + energy
ADP becomes ATP when a free phosphate attaches to the ADP molecule
The energy required to attach the phosphate to ADP is much less than then energy produced when the phosphate bond is broken
ADP + phosphate + energy  ATP

6. ATP – ADP cycle

7. ATP – ADP cycle