In the cell, energy released by electrons is often used to phosphorylate which molecule?

In cellular respiration and various metabolic pathways, energy released by electrons during processes like glycolysis and the electron transport chain is primarily used to phosphorylate ADP to form ATP. ADP, or adenosine diphosphate, serves as the essential substrate that undergoes phosphorylation in order to produce ATP, which is the primary energy carrier in cells.

The phosphorylation of ADP to ATP is a crucial step in cellular energy metabolism because ATP is utilized to power numerous cellular processes, including biosynthesis, transport, and motility. The energy from electrons, derived from organic compounds during catabolic reactions, is harnessed by cellular enzymes to facilitate this phosphorylation reaction, enhancing the pool of available ATP in the cell.

While GTP, AMP, and ATP can also play roles in energy transfer and signaling, the specific process of converting ADP into ATP using energy released by electrons makes ADP the molecule that is directly phosphorylated in this context.