Electron Transport Chain

Question 1

Oxidative Phosphorylation is oxygen dependent?

Answer 1

True

Question 2

Where does the ETC and Oxygen phosphorylation take place?

Answer 2

Inner Mitochondial membrane

Question 3

Reduced Carriers?

Answer 3

NADH

FADH2

Question 4

ATP equivalents of NADH

Answer 4

3 ATP

Question 5

ATP equivalents of FADH2

Answer 5

2 ATP

Question 6

ATP equivalents of GTP?

Answer 6

1 ATP

Question 7

How many sets of Electron transfer systemms and ATP synthas molecules in the inner mito membrane?

Answer 7

over 10,000!

Question 8

Why do we need Mitochondria?

Answer 8

ATP biosynthesis
Mediation of cell death by apoptosis
Heat production (thermogenesis)
Intermediary metabolism (e.g. TCA cycle, fatty acid metabolism)
Genetics (maternal inheritance)

Question 9

How many complexes are there in the ETC?

Answer 9

Four

Question 10

Complex 1 of the ETC
Name?
what does it have?
Does it pump protons?

Answer 10

NADH dehydrogenase
thus oxidizes to NAD +
It pumps protons and has Fe

Question 11

Complex 2 of the ETC
Name?
what does it have?
Does it pump protons?

Answer 11

Succinate Dehydrogenase
succinate to fumarate
FADH2 used
Fe
Heme
no protons pumped

Question 12

Complex 3 of the ETC
Name?
what does it have?
Does it pump protons?

Answer 12

cytochrome b-c1
Fe
Heme
pumps protons

Question 13

Complex 4 of the ETC
Name?
what does it have?
Does it pump protons?

Answer 13

Cytochrome C oxidase
Cu
Heme

Question 14

Complex one is blcked by?

Answer 14

Rotenone

Question 15

Complex 3 blocked by?

Answer 15

Antimycin

Question 16

Complex 4 blocked by?

Answer 16

cyanide and carbon monoxide

Question 17

Iron deficiency affects ?

Answer 17

1,2,3

Question 18

Uncoupler

Answer 18

hydrophobic, moves protons in both directions

Question 19

Respiration (consumption of oxygen) proceeds ONLY when

Answer 19

ADP is present

Question 20

Oxidation of substrates is coupled to the phosphorylation of?

Answer 20

ADP-ATP- O2 consumption

Question 21

The amount of O2 consumed depends on ?

Answer 21

the amount of ADP added

Question 22

2,4 Dintrophenol

Answer 22

increases oxygen consumption

Question 23

oligomycin

Answer 23

ATP synthase inhibitor

increases O2 consumption

Question 24

Chemiosmotic Theory

Answer 24

proton motive force is responsible for driving the synthesis of ATP

Question 25

Proton gradient

Answer 25

Lower pH in the intermembrane
and
High pH in matrix of the mitochondria

Question 26

4 Tenents of Chemiosmotic Theory

Answer 26

1. Inner mitochondrial membrane is impermeable to protons
2. Protons are pumped vectorially across inner mitochondrial membrane
3. Electron transport and ATP synthesis are tightly coupled
4. Presence of an ATP synthase

Question 27

F1F0 - ATP synthase and energy metabolism

Answer 27

F0 subunit in the membrane
and
F1 as the head group

Question 28

Which complex is the major source of ROS production?

Answer 28

Complex 3
Coenzyme
is unstable intermediates of the Q cycle can lead to superoxide formation

Question 29

Protection against ROS

Answer 29

superoxide dismutase SOD

and catalse

Question 30

The _________ transport chain comprises a series of 4 protein complexes (Complexes I-IV) together with coenzyme Q and cytochrome c that are part of the inner mitochondrial membrane. The complexes function to ______reducing equivalents from reduced coenzymes (NADH, P/O ratio=?) or substrates such as succinate/ FADH2(P/O ratio=?) to O2 with the formation of H2O and the ______________________

Answer 30

The mitochondrial electron transport chain comprises a series of 4 protein complexes (Complexes I-IV) together with coenzyme Q and cytochrome c that are part of the inner mitochondrial membrane. The complexes function to transfer reducing equivalents from reduced coenzymes (NADH, P/O ratio=3) or substrates such as succinate/ FADH2(P/O ratio=2) to O2 with the formation of H2O and the generation of a H+/voltage gradient across the inner mitochondrial membrane

Question 31

The ________ involves various prosthetic groups including FAD, FMN, Fe/S clusters, various cytochromes (a, b and c) and Cu. Reducing equivalents are successively transferred from groups of ___________ to those of _____________ coupled with the transport of H+ across the membrane from the matrix to the intermembrane space.

Answer 31

The electron transport chain involves various prosthetic groups including FAD, FMN, Fe/S clusters, various cytochromes (a, b and c) and Cu. Reducing equivalents are successively transferred from groups of low redox potential (NADH) to those of higher redox potential (O2) coupled with the transport of H+ across the membrane from the matrix to the intermembrane space.

Question 32

Mitochondrial function can be blocked at specific sites by the addition of inhibitors of electron transfer such as ?

Answer 32

Mitochondrial function can be blocked at specific sites by the addition of inhibitors of electron transfer such as:

• rotenone
• cyanide
• carbon monoxide or hydrogen sulfide (sewer gas)

Question 33

In functional mitochondria, ____________ (the production of ATP, using the H+/voltage gradient across the inner mitochondrial membrane as a driving force) ________________and regulated by substrate and product availability.

Answer 33

In functional mitochondria, electron transport and oxidative phosphorylation (the production of ATP, using the H+/voltage gradient across the inner mitochondrial membrane as a driving force) are tightly coupled and regulated by substrate and product availability.

Question 34

ATP synthesis is catalyzed by the________, the integral membrane complex that synthesizes ATP from ADP and inorganic phosphate (Pi).

Answer 34

ATP synthesis is catalyzed by the F1/F0 synthase, the integral membrane complex that synthesizes ATP from ADP and inorganic phosphate (Pi).

Question 35

Mitochondrial diseases are?

Answer 35

Maternal Inheritance!