👉 In biology, a phosphagen is a type of molecule that can be converted into ATP through a process called cellular respiration. This process occurs in the mitochondria and cytoplasm of cells, where it involves the breakdown of adenosine triphosphate (ATP), which is stored as a chemical energy in the cell. Phosphagen molecules are not a specific term but rather describe a type of molecule that can be used to generate ATP. This process is crucial for cellular respiration,