Lecture 29 - Oxidative phosphorylation: Electron Transport Chain Flashcards
What are the two processes coupled to produce oxidative phosphorylation?
Electron transport via the electron transport chain and the phosphorylation of ADP to ATP by ATP synthase
What are the two reactions coupled by?
A proton gradient
What is the electron transport chain?
The process where electrons from NADH2 and FADH are passed through a series of carriers, to pump protons into the inter-membrane space of the mitochondria and create a H+ gradient
Where is the electron transport chain?
On the inner membrane of the mitochondria
How do we know the ETC is in the inner membrane?
Isolated mitochondria were treated with a strong and mild detergents to solubilise all and only the outer membranes respectively. When there are no membranes, the ETC does not work. Then there is no outer membrane, the ETC does work. Therefore the ETC is situated on the inner membrane
What is the ETC organised into?
Four complexes labeled I to IV
What does each complex contain?
Multiple carriers
What are the two mobile carriers?
UQ and cyt c
What happens to each carrier in the ETC?
Each carrier accepts electron(s) to be reduced in one redox reaction and then donates electron(s) to be oxidised in another redox reaction
Where do electrons move?
Electrons move from lower to higher reduction potential
What happens when electrons move to carriers with a higher reduction potential?
Energy is released
What has the highest reduction potential?
Oxygen
What happens to electrons as they move through the carriers?
As electrons move to carriers with a higher reduction potential energy is released
Is the ETC energetically favourable to unfavourable
Favourable
What is the energy released as electrons move down the ETC used for
To move protons across the mitochondrial membrane