Oxidative Phosphorylation Overview

Question 1

Desscribe ATP production by oxidative phosphorylation

Answer 1

little amounts of ATP are generated during glycolysis and TCA cycle:

1. 4 ATP/glucose molecule, 2 from glycolysis and 2 from the TCA cycle
2. 90% of the potential free energy present in a molecule of glucose is conserved in reduced coenzymes (10 NADH and 2 FADH2) produced during the full oxidation of a glucose molecule to CO2.
3. The reducing power of these coenzymes is used to synthesize ATP.

4.These coenzymes are reoxidized by oxidative phosphorylation

Question 2

Oxidative phosphorylation is referred to as

Answer 2

ultimate energy transducing system in the cell

Question 3

Name 2 characteristics of oxidative phosphorylation

Answer 3

1. Electrons from NADH and FADH2 will be transferred to a series of electrons carriers from the respiratory chain also known as the electron transport chain (ETC).
2. Oxygen is the final acceptor of the ETC and is reduced to H2O in the process.

Question 3

Name 2 characteristics of oxidative phosphorylation

Answer 3

1. Electrons from NADH and FADH2 will be transferred to a series of electrons carriers from the respiratory chain also known as the electron transport chain (ETC).
2. Oxygen is the final acceptor of the ETC and is reduced to H2O in the process.

Question 4

What are the 2 steps of oxidative phosphorylation

Answer 4

1. Oxidation
   -Electrons transfer chain (ETC) involving Complex I to IV
2. Phosphorylation
   - ATP synthesis involving Complex V

Question 5

What is the chemiosomotic theory

Answer 5

There is a coupling between oxidation and phosphorylation created by a proton gradient on either side of the inner mitochondrial membrane:
-Chemical energy (oxidation) is converted in osmotic energy via transmembrane protein complexes, creating a proton gradient between the mitochondrial intermembrane space and the mitochondrial matrix
-Complexes I, III et IV = proton pumps
-Osmotic energy (proton gradient) converted back into chemical energy (phosphorylation) via ATP synthase

Question 6

Describe the hoover dam analog in regard to the electron transport chain

Answer 6

-Water stored behind the dam = Mitochondrial Proton-motive force
-ETC is in charge of generating the mitochondrial Proton-motive force

-Water intake tower and turbine = ATP synthase
-ATP synthase will use the mitochondrial Proton-motive force to generate ATP