Lecture 27: The Electron Transport Chain

Question 1

during the citric acid cycle, NAD+ and FAD are ___ to NADH and FADH2 and acetyl CoA is ___ to CO2

Answer 1

reduced; oxidized

Question 2

__ and __ carry electrons to the terminal ETC

Answer 2

NADH and FADH2

Question 3

the ETC ultimately reduces __ to __

Answer 3

molecular oxygen to H2O

Question 4

as electrons are transferred through a series of ___ in the mitochondria cristae, protons are transferred across the __

Answer 4

4 large proteins; membrane `

Question 5

the unequal distribution of protons across a membrane is a source of ___ called the __

Answer 5

potential energy; Proton Motive Force

Question 6

the energy of the proton motive force is used to __

Answer 6

make ATP

Question 7

the ETC is a suite of ___ and __ mainly organized into 4 large complexes

Answer 7

membrane proteins and organic molecules

Question 8

NADH delivers electrons to complex ___ and FADH2 delivers to complex __

Answer 8

I; II

Question 9

besides the 1st two complexes, NADH and FADH2 travel the exact same path (t/f)

Answer 9

true

Question 10

as electrons thrive through the chain, they go from a higher to lower level, so energy is ___

Answer 10

released

Question 11

complexes I, III and IV pump ___ from the mitochondria matrix to the inter membrane space

Answer 11

protons

Question 12

the concentration of protons is higher in the ___ than ___

Answer 12

inter membrane space ; matrix

Question 13

protons flow back into the matrix by the ___ to equalize the distribution

Answer 13

ATP synthase

Question 14

most of the TCA enzymes are floating in the ___, but succinate dehydrogenase is in the ___

Answer 14

matrix; inner membrane

Question 15

which complex is succinate dehydrogenase?

Answer 15

complex 2

Question 16

complex 2 is a physical link between the ___ and the ___

Answer 16

TCA cycle and the ETC

Question 17

within a complex, each time an e- jumps from one redox centre to another, ___

Answer 17

some energy is released

Question 18

what are 2 mobile components of the ETC?

Answer 18

coenzyme Q (ubiqiunone) and cytochrome C

Question 19

what is coenzyme Q (ubiquinone)?

Answer 19

organic molecule delivering e- from complexes 1 and 2 to complex 3

Question 20

what is cytochrome C?

Answer 20

protein delivering e- from complex 3 to 4

Question 21

the proton motive force is a ___ gradient that constitutes potential energy

Answer 21

electrochemical

Question 22

Protons flowing down their concentration gradient powers ___that catalyses the reaction that makes ATP

Answer 22

ATP synthase

Question 23

does FADH2 or NADH have a higher reducing potential?

Answer 23

NADH

Question 24

10 NADH makes ___ ATP

Answer 24

30

Question 25

2 FADH2 makes ___ ATP

Answer 25

4