Explain why ATP is the chosen energy currency of cells First

Explain why ATP is the chosen energy currency of cells. Firstly, use a description of the structural features of ATP that explain why it is an ideal energy Secondly, explain why energy is not just provided by the simple hydrolysis of ATP.

Solution

ATP is ideal energy currency because ATP can easily release and store energy by breaking and re-forming the bonds between its phosphate groups. It is like a fully charged battery and has more bonds available for energy storage. ATP syntheses can efficiently reattach the Pi to ADP.

The phosphate groups in ATP are full of negative charges and these are repelling one another. This means that the third phosphate is a great leaving group and breaking the phosphor-anhydride bond is a favorable reaction.

Food is broken down into glucose molecules. By burning glucose in the mitochondria of cells, energy is released to make ATP from adenosine di-phosphate and free phosphate molecules. This process is called glycolysis. As ATP molecules are used, more ATP are generated in the mitochondria by adding a phosphate group to the ADP molecule. This is a major part of the Krebs cycle.

The chemical reaction of cleaving off each phosphate group from ATP yields energy. The most important bond is between the second and third phosphate groups. The process of taking off the third phosphate group yields 7.3 kilocalories of energy per mole. When additional energy is needed, the cleaving of another phosphate group from ADP to yield adenosine mono-phosphate provides more energy