Respiration: Oxidative Phosphorylation S3

Question 1

What molecules are used in the oxidative phosphorylation cycle?

Answer 1

In oxidative phosphorylation the coenzymes reduced NAD and reduced FAD are used

Question 2

Where does oxidative phosphorylation occur?

Answer 2

Occurs in the mitochondrial inner membrane cristae

Question 3

What are the steps involved in oxidative phosphorylation?

Answer 3

1. Coenzymes NAD and FAD combine with hydrogen atoms. They become reduced and donate their electrons from the hydrogen atoms to the first molecule in the electron transfer chain.
2. The electrons are then passed along the electron transfer chain in a series of redox reactions, which cause the active transport of protons to the inter membrane space
3. This continues allowing the protons to accumulate in the inter membrane space. The protons eventually diffuse back into the mitochondrial matrix through facilitated diffusion through ATP synthase.
4. This movement catalyses the phosphorylation of ADP to form ATP
5. Oxygen atoms will combine with electrons and hydrogen atoms to form water. The oxygen acts as a final acceptor of electrons in the electron transfer chain

Question 4

Why is oxygen important in the respiration reaction?

Answer 4

Oxygen acts as a final acceptor of hydrogen atoms and electrons produced in the cycle. Without its role of removing hydrogen atoms at the end of the chain, the hydrogen ions and electrons would back up along the chain and the process of respiration would stop entirely