Aerobic respiration: Oxidative Phosphorylation

Question 1

what is are the functions of O.P? (2)

Answer 1

1. produce more ATP as glycolysis and krebs cycle only produce small amt (4 ATP)
2. regenerate NAD+ and FAD for other stages. w/o the regeneration, glucose oxidation unable to continue

Question 2

where does OP take place?

Answer 2

inner mitochondrial membrane

Question 3

what are the 4 stages of OP?

Answer 3

1. NADH and FADH2 donate electrons to electron carriers and get reoxidised to NAD+ and FAD. Protons released in matrix
2. electrons passed along ETC from higher energy carrier proteins to lower energy carrier proteins
   - release energy to pump protons to intermembrane space
   - create proton gradient
3. o2 serves as final electron and proton acceptor, gets reduced to h2o, reoxidising ETC
4. protons diffuse down concentration gradient thru ATP synthase, energy transferred to ADP to form ATP

Question 4

what is the role of o2 in OP? (3)

Answer 4

1. final electron and proton acceptor that reoxidises ETC, allow OP to continue
2. . allow for regeneration of NAD+ and FAD
3. removes protons (thru h2o formation) to maintain proton gradient

Question 5

how many ATP is produced thru OP?

Answer 5

10 x 2.5 + 2 x 1.5 = 28 ATP

10 NADH and 2 FAD2 from prev. stages

Question 6

what is the total ATP produced in aerobic respiration? (in terms of co2, ATP, NADH, FADH2)

Answer 6

glycolysis: 2 ATP , 2NADH
link reaction: 2 co2, 2 NADH
krebs cycle: 4 co2, 2 ATP , 6 NADH, 2 FADH2
total: 6 co2, 4 ATP, 10 NADH, 2 FADH2
total ATP including OP: 4 ATP, 28 ATP
total ATP: 4 + 28 = 32 ATP