Final answer:
ATP functions as the primary energy currency for cells, providing the energy needed for various processes like muscle contraction and active transport. The energy is released when ATP is hydrolyzed, with its terminal phosphate group removed and transferred to other molecules, in a process known as phosphorylation.
Step-by-step explanation:
Role of ATP as Cellular Energy Currency
The role of ATP (adenosine triphosphate) is to serve as the energy currency for cells, enabling them to store and transfer energy within themselves. ATP is crucial for various cellular processes. For instance, ATP is needed to build organic molecules, provides energy for muscle contraction, assists in electrical signal transmission, and functions as the body's fuel source. Additionally, ATP plays a vital role in active transport, such as the action performed by the sodium-potassium pump, where it helps pump ions against their electrochemical gradients.
Energy Release through Hydrolysis of ATP
Energy is released through the hydrolysis of ATP when the terminal phosphate group is detached, often resulting in ADP (adenosine diphosphate) and a free phosphate group. The energy from ATP hydrolysis is utilized for cellular work by binding the released phosphate to another molecule, thereby activating it. This process, whereby ATP donates its phosphate group to another molecule, is known as phosphorylation. During muscle contraction, the energy supplied by ATP is used to move the contractile proteins, illustrating the transfer of energy within the cell.