The fundamental process where living organisms derive energy from the transfer of electrons, typically involving the removal of hydrogen atoms. This often entails the combination of a substance with oxygen, though the electron transfer can occur independently of oxygen. A classic example is the breakdown of glucose in cellular respiration, where glucose molecules are progressively dehydrogenated, releasing energy stored in their chemical bonds to power cellular activities.
This process is essential for sustaining life, enabling organisms to synthesize ATP, the primary energy currency of cells. The controlled release of energy through gradual steps prevents uncontrolled combustion and allows for efficient energy capture. Throughout evolutionary history, it has facilitated the development of complex metabolic pathways, enabling organisms to thrive in diverse environments and perform a vast array of biological functions. Its understanding has also underpinned advancements in fields like medicine and biotechnology.