Why is oxygen crucial for aerobic respiration?

Oxygen is crucial for aerobic respiration because it serves as the final electron acceptor in the electron transport chain. During this process, electrons that are generated from the breakdown of glucose are transferred through a series of carriers in the inner mitochondrial membrane. At the end of this chain, oxygen combines with the electrons and protons to form water. This step is vital because it helps maintain the flow of electrons through the chain, allowing for the continued production of ATP through oxidative phosphorylation. Without oxygen, the electron transport chain would halt, leading to a significant decrease in ATP production and ultimately affecting the cell’s ability to perform various functions that rely on energy.