Describe the structure and uses of ATP.

ATP (Adenosine Triphosphate) is a nucleotide consisting of adenine (a nitrogenous base), ribose (a five-carbon sugar), and three phosphate groups. The energy in ATP is stored in the bonds between the phosphate groups. When a cell needs energy, it breaks the bond between the second and third phosphate groups, releasing energy and converting ATP to ADP (Adenosine Diphosphate) and inorganic phosphate. ATP is used in various cellular processes, including muscle contraction, protein synthesis, DNA replication, and active transport across membranes. The constant regeneration of ATP from ADP ensures that cells have a continuous supply of energy for their metabolic needs.