How is energy stored in the ATP molecule?
ATP stands for “adenosine triphosphate”, which means that it is an adenosine molecule with three phosphate groups attached to it. You can do a google image search to find a diagram of what it looks like. There should also be a picture in your textbook. It requires energy to attach a third phosphate group to ADP (adenosine diphosphate, with only 2 phosphate groups). When you eat food, your body burns it and uses the energy from the food to attach a 3rd phosphate group to an ADP molecule to turn it into an ATP molecule. This happens inside the mitochondria. The newly-formed ATP then goes to somewhere else in the cell, where energy is needed. When it gets there, a protein takes that 3rd phosphate group off of the ATP, turning it back into ADP. Because it required energy to put the phosphate group on in the first place, taking it off again gives that energy to the protein that took it back off. In this way, ATP stores energy from food, transports it to another part of the cell, and then gi
