Oxidative Phosphorylation

Question 1

Oxidative phosphorylation occurs in the ???

Answer 1

matrix

Question 2

the electron transport chain is embedded in the ??? of the mitochondria

Answer 2

the INNER mitochondrial membrane

Question 3

Complex I is called ???

Answer 3

NADH dehydrogenase

Question 4

Complex II is called ???

Answer 4

Succinate dehydrogenase

Question 4

Complex III is called ???

Answer 4

Ubiquinone:cytochrome c
oxidoreductase

Question 5

Complex IV is called ???

Answer 5

cytochrome oxidase

Question 6

Complex V is the ATP synthase and is the ??? component of oxidative phosphorylation

Answer 6

phosphorylation

Question 7

Which complex doesn’t do H ion pumping?

Answer 7

Complex II

Question 8

Which complex(es)
exhibit Fe-S centers?

Answer 8

Complexes I, II, III

Question 9

How many electrons do the complex(es)
exhibiting Fe-S centres carry?

Answer 9

1 electron (Ubiquinone by itself carries 2 e)

Question 10

Name the amino
acid the Fe-S exhibiting complexes are bound to

Answer 10

Cysteine

Question 11

TRUE or False: coenzyme Q (Ubiquinone) carries 2 electrons

Answer 11

True

Question 12

What is the final e– acceptor of the ETC?

Answer 12

oxygen

Question 13

Coenzyme Q (Ubiquinone) is ??? and can OR can’t freely diffuse within the
lipid bilayer of the inner
mitochondrial membrane?

Answer 13

lipid soluble, CAN freely diffuse

Question 14

Coenzyme Q (Ubiquinone) Can OR Can’t shuttle reducing equivalents between other less mobile components?

Answer 14

It can

Question 15

Cytochrome C is a soluble or insoluble heme-containing protein in the intermembrane space

Answer 15

soluble

Question 16

Cytochrome C is a ??? carrier

Answer 16

mobile electron

Question 17

Complex I to Complex IV reaction for NADH:
1 NADH, ???H (M) + ½O2 —> NAD+ + ???H+ (IMS) + H2

Answer 17

11 H+ ions to 10H+ ions

Question 18

Complex II to Complex IV reaction for FADH:
FADH2 + ???H+ (M) + ½O2 —> FAD + ???H+ (IMS) + H2O

Answer 18

6H+ ions to 6H+ ions

Question 19

What is the purpose of dehydrogenations of NADH, FMNH2, FADH2 and the reactions oxidising Coenzyme Q and Cytochrome C?

Answer 19

They pump protons (H+) into the
intermembrane space which is used to set up an electrochemical gradient

Question 20

why is an electrochemical gradient set up?

Answer 20

to drive ATP synthesis

Question 21

the FO component of ATP synthase is the ??? spanning domain

Answer 21

membrane-spanning domain

Question 22

The FO component of ATP synthase transports H+ from IMS to ???,
dissipating the proton gradient.

Answer 22

matrix

Question 23

the O in FO comes from ??? sensitivity.

Answer 23

oligomycin

Question 24

Energy transferred from ??? to F1 to catalyze phosphorylation of ADP

Answer 24

FO to F1

Question 25

F1 component of ATP synthase is the ATP ??? domain and a soluble complex in the matrix

Answer 25

ATP synthesizing domain

Question 26

In ATP synthase, A total of ??? H+ are transported per ATP generated by ATPase

Answer 26

A total of 3 H+ are transported per ATP

Question 27

TRUE or FALSE: An extra H+ is used by ATPase to transport phosphate (H2PO4- is required for ATP synthesis)

Answer 27

TRUE

Question 28

Binding-Change model of ATPase: proton-motive force causes rotation of the ??? —the γ subunit

Answer 28

central shaft

Question 29

ATPase: the γ subunit contacts each αβ subunit pair in succession. = ??? which ejects ATP from the β-ATP site. The β-ADP site is converted to the β-ATP conformation, which promotes condensation of bound ADP + Pi to form ATP

Answer 29

conformational change

Question 30

Oxidative phosphorylation can be discoupled by: ??? (such as digitonin), chemicals such as dinitrophenol, an uncoupling protein

Answer 30

disrupting membranes with detergents

Question 31

Non-shivering thermiogenesis: The inner membrane of brown fat mitochondria is very permeable to H+ and UCPs allow H+ leak back across the inner membrane. Heat is produced instead of ???

Answer 31

ATP

Question 32

UCP1 reduces the number of ??? that can be made from a given amount of food, raising the body’s metabolic rate and generating heat.

Answer 32

ATPs

Question 33

UCP2 is expressed in brain, fat, muscle, and b-cells of the pancreas. UCP3 is expressed mostly in ???

Answer 33

muscle