Cellular Respiration Pt. 2

State the location of the ETC

• inner mitochondrial membrane

Explain how the intermembrane cristae help the ETC

• inc. SA available for the transport chain, embedding in more ETC proteins and ATP synthase

• increasing the rate and efficiency

State the purpose/end goal of the ETC

• Oxidative phosphorylation: releases the energy stored within the reduced hydrogen carriers via oxidation in order to synthesize ATP

Outline the steps of the ETC Pt. 1

Proton Motive Force

1) The hydrogen carriers (NADH and FADH2) are oxidized => release high energy electrons and H+

2) e- and H+ are transferred to transmem carrier proteins

3) e- energy used to pump H+ from the matrix

4) Accumulation of H+ ions within the intermembrane space => electrochemical gradient

Outline the steps of the ETC Pt. 2

Chemiosmosis

5) Proton Motive Force will cause H+ ions to move down there electrochemical gradient and diffuse back into the matrix (chemiosmosis, which is facilitated by ATP synthase)

6) H+ ions move through ATP synthase => trigger rotation => synthesizing ATP

Outline the steps of the ETC Pt. 3

Reduction of Oxygen

7) De-energized electrons must be removed for ETC to keep functioning

8) Oxygen is the final electron acceptor, removing de-energized eletrons (prev. blocking)

9) Oxygen binds w/ free protons in the matrix => water, maintaining H+ gradient

10) W/o oxygen, hydrogen carriers cannot transfer energized electrons to the chain and ATP production is halted