EVERYDAY SCIENCE

Detailed explanation-1: -Adenosine triphosphate (ATP) is the source of energy for use and storage at the cellular level. The structure of ATP is a nucleoside triphosphate, consisting of a nitrogenous base (adenine), a ribose sugar, and three serially bonded phosphate groups.

Detailed explanation-2: -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-3: -ATP consists of an adenosine molecule bonded to three phosphate groups in a row. During cellular respiration, energy in food is converted into chemical energy that can be used by cells. This chemical energy is stored in the pyrophosphate bond, which lies between the last two phosphate groups of ATP.

Detailed explanation-4: -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-5: -When the cell needs energy to do work, ATP loses its 3rd phosphate group, releasing energy stored in the bond that the cell can use to do work. Now its back to being ADP and is ready to store the energy from respiration by bonding with a 3rd phosphate group. ADP and ATP constantly convert back and forth in this manner.