Electron Transport Chain

Question 1

What is Complex I and What are the chain the electrons go?

Answer 1

NADH dehydrogenase. NADH to FMN to FeS clusters to Coenzyme Q (CoQ - CoQH2)

Question 2

What are some properties of CoQ?

Answer 2

It is lipid soluble and exists in the inner mito membrane. Single electron transfers from CoQ to O2 are a major source of ROS.

Question 3

What complexes directly intreat in the ETC?

Answer 3

I, III, and IV

Question 4

What is the electron flow in complex II SDH?

Answer 4

Succinate to Fumarate make FADH2. FADH2 to CoQ

Question 5

What is the electron flow to Complex III?

Answer 5

CoQH2 gives its electrons to CytB then CytB to Fe-S cluster then to free floating CytC.

Question 6

What is the name of Complex III?

Answer 6

cytochrome b c1

Question 7

What is the name of complex IV?

Answer 7

cytochrome c oxidase

Question 8

What is the flow of electrons in complex IV?

Answer 8

free CytC gives to CytA. CytA to CytA3. CytA3 gives electrons to free O2 converting it to H2O.

Question 9

How many hydrogens does each complex pump into the inter membrane space?

Answer 9

Complex I and III:4, Complex II:0, Complex IV:2

Question 10

What is a superoxide?

Answer 10

O2-

Question 11

How is a hydroxyl radical formed?

Answer 11

H2O2-H2O + OH radical

Question 12

What is the Haber-Weiss reaction?

Answer 12

none enzymatic. superoxide+H202 to O2+H2O+hydroxyl radical.

Question 13

What is the Fenton reaction?

Answer 13

H2O2 to OHrad+OH- by Fe

Question 14

What is the ATPase structure?

Answer 14

F1 is in the matrix: 12C subunits

F2 in in the inner membrane: 3 alphabet pairs.

Question 15

How is heat generated form the normal formation of ATP during ETC?

Answer 15

by the extra energy of the NADH to H2O reaction.

Question 16

What are the three uncouplings of the ETC

Answer 16

Adaptive thermogenesis, chemical uncoupling, and mechanical uncoupling.

Question 17

How does Adaptive thermogenesis work?

Answer 17

when it’s cold norepinephrine activates hormone sensitive lipase in brown fat cells. Also a proton channel called thermogenin (UCP1) is also activated which generates heat as it allows H+ to travel down it’s gradient.

Question 18

What is the prototypical chemical uncoupler?

Answer 18

Dinitrophenol

Question 19

How does mechanical uncoupling occur?

Answer 19

ROS and mito swelling. protons then leak through holes

Question 20

Where does the energy for H+ transport come from?

Answer 20

the electrochemical gradient because the matrix side is - charged. the pH gradient

Question 21

Example of an anti porter?

Answer 21

ATP/ADP

Question 22

Example of a symporter?

Answer 22

pyruvate+H+ and Pi+H+

Question 23

Example of a uniporter?

Answer 23

calcium

Question 24

What is VDAC?

Answer 24

Voltage dependant ion channel

Question 25

What causes and what is a mitochondrial permeability transition pore (MPTP)?

Answer 25

A pore that forms under hypoxia that is composed of ANT and VDAC that causes depolarization of the membrane gradients and proton gradients. Leads to apoptosis and necrosis.