The molecular structure of ATP (adenosine triphosphate) consists of an adenine base, a ribose sugar, and three phosphate groups. These phosphate groups are connected by high-energy bonds; thus, when one phosphate group is hydrolyzed (removed), it releases energy for cellular processes. ATP is often referred to as the cell's energy currency, as it plays a crucial role in driving biochemical reactions, muscle contractions, and biosynthetic pathways. The regeneration of ATP from ADP (adenosine diphosphate) and inorganic phosphate is essential for sustaining cellular energy requirements.