Mitochondrial Electron Transport and ATP generation

Question 1

Complex I

Answer 1

NADH-CoQ reductase, NADH oxidized to NAD+ and CoQ reduced to CoQH2

Question 2

Complex II

Answer 2

Succinate-CoQ reductase. Succinate oxidized to fumarate and CoQ reduced to CoQH2

Question 3

Complex III

Answer 3

CoQH2- cytochrome C reductase. CoWH2 oxidized to CoQ and 2 C of cytochromes is reduced

Question 4

Complex IV

Answer 4

cytochrome c oxidase. 4 cyt c is oxidized (Fe2+ to Fe3+) and O2 is reduced to water. Cu fluctuates between Cu2+ and Cu3+

Question 5

Which complexes are proton pumps

Answer 5

I, III, and IV

Question 6

What’s the prosteic group of cytochrome c

Answer 6

iron

Question 7

How many ATP result from oxdization of NADP

Answer 7

3 ATP

Question 8

Fo

Answer 8

inner membrane proton channel

Question 9

F1

Answer 9

catalyzes ATP synthesis from ADP

Question 10

Chemiosmotic coupling model of ATP production

Answer 10

free energy released from ETS drives an active transport system that pumps H+ out of matrix and across inner membrane = electrochemical gradient. When these H+ flow down their conc gradient the free enrgy is trapped, used to reverse reaction of ADP to ATP

Question 11

Cyanide

Answer 11

inhibits ETS. Blocks complex IV. Causes lactic acidosis and death by respiatory arrest.

Question 12

CO

Answer 12

inhibits ETS. reacts with Hb and prevents loading of oxygen. Causes lactic acidosis and lack of oxygen to tissues

Question 13

DNP

Answer 13

uncouples of oxidative phosphorylation. ETS flow works, but ATP is not made. End up with hyperthermia, nausea, sweating, fever

Question 14

Aractylsodie

Answer 14

inhibitor of adenine nucleotide translocase found in inner membrane of mitochondrion to transport ATP out of other cells. Exchange ATP out for ADP in

Question 15

uncoupling proteins

Answer 15

provider alternate route for re-entry of protons into mitochondrial matrix. Bypass ATP synthase channel, causing no ATP to be made

Question 16

How does ATP leave mitochondria

Answer 16

through adenine translocatse located in inner mitochondria.

Question 17

How does pyruvate get from cytoplasm into mitochondrion

Answer 17

pyruvate carrier

Question 18

Serum Lactic acidosis

Answer 18

defect in complexes i-IV, causes ETS to stop working, inhibits ATP formation, causes buildup of CAC intermiedate and pyruvate. Pyruvate gets converted into lactic acid

Question 19

LHON

Answer 19

sudden blindness due to mutation in complex I

Question 20

MERRF

Answer 20

seizures and skeletal muscles effected. Cytochrome oxidase inhibited.

Question 21

MELAS

Answer 21

muscle specifmens affected. cytochorome oxidase normal. point mutation in leucine tRNA