AP BIOLOGY

Detailed explanation-1: -The phosphate tail of ATP is the actual power source which the cell taps. Available energy is contained in the bonds between the phosphates and is released when they are broken, which occurs through the addition of a water molecule (a process called hydrolysis).

Detailed explanation-2: -ATP stands for adenosine triphosphate. The word triphosphate indicates that the molecule has 3 phosphate groups. ATP stores energy within the bonds between phosphate groups, especially the second and third. This bond is a source of potential chemical energy, and it’s kind of like a compressed spring.

Detailed explanation-3: -The last phosphate bond holds the most energy (approx. 7 kcal/mole). It is called the pyrophosphate bond. In order to release it’s energy to the body, ATP breaks down into ADP [Adenosine Diphosphate(2 phosphates)] and an inorganic phosphate group and releases energy from the pyrophosphate bond.

Detailed explanation-4: -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.

Detailed explanation-5: -These bonds are high energy because of the associated electronegative charges exerting a repelling force between the phosphate groups. A significant quantity of energy remains stored within the phosphate-phosphate bonds.