18.4 Oxidative Phosphorylation

Question 1

Describe oxidative phosphorylation. (4 marks)

Answer 1

1. NADH and FADH2 deliver hydrogen atoms to electron transport chain (ETC).
2. The hydrogen atoms dissociate into hydrogen ions and electrons.
3. The electrons are used to make ATP by chemiosmosis.
4. At then end of then ETC, the electrons and hydrogen ions combine with oxygen to form water.

Question 2

Where ate the electron transport chains? (1 mark)

Answer 2

In the membranes cristae of the mitochondria.

Question 3

Where do the hydrogen atoms come from? (1 mark)

Answer 3

NADH and FADH2

Question 4

Where have the NADH and FADH2 come from? (! mark)

Answer 4

The Krebs cycle

Question 5

What do then hydrogens dissociate into? (1 mark)

Answer 5

Hydrogen ions (protons) and electrons

Question 6

How is ATP synthesised in oxidative phosphorylation? (1 mark)

Answer 6

Chemiosmosis

Question 7

At the end of the electron transport chain, how is water formed? (2 marks)

Answer 7

The electrons and hydrogen ions combine with oxygen.

Question 8

What is then final electron acceptor in oxidative phosphorylation? (1 mark)

Answer 8

Oxygen

Question 9

What is the phosphorylation of ADP to ATP dependent on? (1 mark)

Answer 9

The electrons moving along the electron transport chain.

Question 10

In oxidative phosphorylation, what type of phosphorylation occurs to produce ATP? (1 mark)

Answer 10

Substrate level phosphorylation