2.6 - Electron Transport Chain (ETC)

Question 1

What co-enzymes are used in ETC?

Answer 1

NAD+ & FAD+

Question 2

Explain the pathway of an electron from NADH.

Answer 2

• electron gets released from NADH (becomes NAD+) at protein 1
• enough energy is created to push out one H+ ion
• electron carrier brings e- to protein 2, rxn releases energy which pumps out an H+
• electron carrier brings e- to protein 3, rxn releases energy, pumps out H+
• to remove e- from protein, it detaches and attaches with oxygen to keep chain moving
• electrochemical gradient is outside and wants to come into the matrix, so H+ gets pushes through ATP synthase which creates ATP

Question 3

How are the proteins/complexes in ETC arranged?

Answer 3

They are arranged from lowest En to highest En

Question 4

How many ATP do NADH and FADH2 produce?

Answer 4

10 NADH @ 3 ATP each
2 FADH2 @ 2 ATP each

Question 5

What is chemiosmosis?

Answer 5

• When an electrochemical gradient is created, forms potenital energy, and wants to go back to where the concentration is lower.
• H+ cannot pass through membrane alone, so it need to pass through a special protein (Ex: in ETC, it’s ATP synthase)
• this movement produces ATP