Oxidative Phosphorylation

Question 1

Why do we need Oxidative Phosphorylation

Answer 1

1.Homeostasis (normal cellular functions)
2.Major source of energy in the form of ATP (RBC exception)

Question 2

Is the ETC exergonic?

Answer 2

Yes, Highly exergonic

Question 3

Q-pool

Answer 3

between 1 and 3 , getting electrons from 1 and 2

Question 4

Coenzyme Q or Ubiquinone is NOT

Answer 4

a protein

Question 5

Step I: Oxidation of NADH by

Answer 5

NADH-Q Oxidoreductase (Complex I)

Question 6

Complex II makes

Answer 6

FADH2 and reduces Q

Question 7

Complex II does not

Answer 7

pump protons!

Question 8

Step II: Complex II contains

Answer 8

Succinate Dehydrogenase from CAC

Question 9

Step III: Complex III

Answer 9

Q Cycle

Question 10

Stage IV: Complex IV

Answer 10

The Reduction of Molecular Oxygen to Water

Question 11

Products of Complex IV

Answer 11

2 waters (reduced O2)
8 H+ out of matrix, 4 to intermembrane space
Cyt cox recycled

Question 12

Products of the ETC

Answer 12

2 waters (reduced O2)
10 H+ out of matrix for NADH (only 6 for FADH2)
electrochemical/pH/proton gradient

Question 13

The Purpose of the Electron Transport Chain is to Create the

Answer 13

Proton Motive Forceaka the “cation gradient”!

Question 14

The World’s Smallest Molecular Motor”

Answer 14

ATP Synthase

Question 15

F0 domain

Answer 15

a rotating proton channel in the membrane

Question 16

F1 domain

Answer 16

stationary ATP Synthase made of nine subunits (a3b3gde)

Question 17

Protons get Pumped Back into the Matrix Through

Answer 17

F0

Question 18

ATP Synthase Can Make ATP without a

Answer 18

Proton Motive Force

Question 19

How many active sites does ATP have

Answer 19

3 Active Sites in the b Subunits in Different Forms

Question 20

Three Active Sites in the b Subunits

Answer 20

T = tight form (yellow)
L = loose form (blue)
O = open form (green)

Question 21

When the g (g) subunit touches a b subunit

Answer 21

, it converts to T and holds onto ATP

Question 22

What drives the formation of the proton motive force

Answer 22

Free energy generated by the reduction of molecular oxygen

Question 23

one NADH could pump out

Answer 23

~ 10 H+

Question 24

need ~ 4 H+ per ATP, so

Answer 24

10/4 = 2.5 ATP/NADH

Question 25

What happens when the Proton Motive Force is disrupted?

Answer 25

Disease (low ATP)
Heat (brown adipose tissue)
Free radical formation (extra e-)