1. Electron Transport Chain

2. Oxidative Phosphorylation
The purpose of the ETC is to create ATP through “Oxidative Phosphorylation”
ATP is created through a series of redox reactions
NADH and FADH2 are produced by steps 1-3 of cellular respiration, and are “electron carriers”

3. Electron Transport Chain
SBI 4U: Metablic Processes
Electron Transport Chain
NADH and FADH2, transfer their electrons (2) to a series of proteins embedded in the inner mitochondrial membrane.
FADH2 enters the chain at the second step
Section 1.3

4. ETC proteins
The proteins are arranged in order of increasing electronegativity
Each protein is reduced by gaining two electrons from the one before it

5. ETC proteins 3 are “proton pumps”
Use the energy from electrons to pump protons (H+) from the matrix to the intermembrane space
Each 2 electrons cause 2 H+ to be pumped out

6. ETC proteins 2 are “electron shuttles”
Transport electrons from one pump to the next

7. ETC and Redox Reactions
The protons pumped out create an electrochemical gradient
There is more positive charge in the intermembrane space than the matrix
H+ want to come back into matrix, but cannot cross inner membrane
Protons flow through ATP synthase, driving it to create ATP
2 protons make 1 ATP

8. Role of oxygen Oxygen is highly electronegative
It is the final electron acceptor
Takes the 2 electrons from the final proton pump, combine with 2 protons in the matrix to form water
What would happen if there isn’t oxygen present?