What is the primary energy currency of cells?

The primary energy currency of cells is adenosine triphosphate, commonly known as ATP. ATP plays a crucial role in cellular processes by storing and transporting chemical energy within cells. It consists of three phosphate groups, and the energy stored in the high-energy bonds between these phosphate groups can be released when ATP is converted to adenosine diphosphate (ADP) and an inorganic phosphate. This release of energy is essential for various cellular activities, including muscle contraction, nerve impulse propagation, and biochemical synthesis.

While molecules like NADH and FADH2 are important for energy production during cellular respiration, they function primarily as electron carriers in the metabolic pathways leading to ATP synthesis. Glucose is a key fuel source for cells, as it is broken down through glycolysis and the Krebs cycle to ultimately produce ATP. However, ATP itself is the direct energy currency that cells use to perform work, making it fundamental to all living organisms.