Question

Which of the following processes make direct use of oxygen?

• A. Glycolysis
• B. Fermentation
• C. Electron transport
• D. Citric acid cycle

Answer 1

The correct option is C Electron transport

Oxidative phosphorylation is made up of two closely connected components: the electron transport chain and chemiosmosis. In the electron transport chain, electrons are passed from one molecule to another, and energy released in these electron transfers is used to form an electrochemical gradient. In chemiosmosis, the energy stored in the gradient is used to make ATP. Oxygen sits at the end of the electron transport chain, where it accepts electrons and picks up protons to form water. If oxygen isn’t there to accept electrons (for instance, because a person is not breathing in enough oxygen), the electron transport chain will stop running, and ATP will no longer be produced by chemiosmosis. Without enough ATP, cells can’t carry out the reactions they need to function, and, after a long enough period of time, may even die.

So, the correct option is 'electron transport'.