Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Bioc 2580 > Electron Transport Chain > Flashcards

Electron Transport Chain Flashcards

1
Q

What is the overall mechanism of the electron transport chain

A

energy released from NADH and FADH2 is used to synthesize ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where does the electron transport chain occur

A

the mitochondria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Oxidation of reduced factors: ___________

A

energetics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Reduced cofactors are passed to oxygen ____________ along the electron transport chain

A

indirectly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Instead of all energy being released at once, what occurs

A

the reoxidation of NADH and FADH2 is broken into several distinct processes
- results in smaller energy changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Electron carriers in ETC are arranged in order of…

A

increasing reduction potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the terminal electron acceptor

A

oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is complex 1

A

NADH dehydrogenase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is complex 2

A

succinate dehydrogenase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is complex 3

A

acyl-CoA dehydrogenase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is complex 4

A

glycerol 3-phosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is another term for coenzyme Q

A

ubiquinone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

If ubiquinone accepts one electron what is formed

A

semiquinone radical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

If ubiquinone accepts two electrons what is formed

A

the alcohol ubiquonol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How are electrons carried from one ETC complex to another

A

ubiquinol can freely move in the membrane, so it carries electrons from one complex to another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Cytochrome C are a family of proteins with iron-containing ____________ prosthetic groups

A

heme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Cytochrome C is a soluble protein found in the _______________ ____________

A

intermembrane space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the function of cytochrome c

A

shuttles electrons from complex 3 to complex 4

19
Q

How many electrons does the heme group on cytochrome c carry at a time

A

one at a time

20
Q

Complex’s 1 and 2 transfer electrons to Q, reducing it to ________

A

QH2

21
Q

QH2 passes electrons to ____________________ through complex 3

A

cytochrome c

22
Q

Complex 4 transfers electrons from reduced cytochrome c to _______

A

O2

23
Q

Electron flow from complex’s 1,3,4 is accompanied by ____________ __________ from the matrix to intermembrane space

A

proton flow

24
Q

In the presence of an electron donor and O2, all carriers occurring before the point of obstruction become _____________ and the carriers beyond the point become ______________

A

before point; become reduced
after point; become oxidized

25
Q

Many of the carriers have distinctive optical ___________________ with different optical spectra under oxidized and reduced states

A

chromophores

26
Q

What is the importance of the optical chromophores

A

allows for identification of the redox state of carriers

27
Q

How many electrons from NADH are pumped

A

10 total
4 by complex 1, 4 by complex 3, and 2 by complex 4

28
Q

How many electrons from FADH2 are pumped

A

6 total
4 by complex 3 and 2 by complex 4 (bypass complex 1)

29
Q

What is the energy stored in the gradient called

A

the proton motive force

30
Q

What are the 2 components of the proton motive force

A
  1. chemical potential energy
  2. electrical potential energy
31
Q

What causes the chemical potential energy in proton motive force

A

difference in H+ concentration

32
Q

What causes the electrical potential energy in proton motive force

A

separation of charges

33
Q

Energy is _____________ in the proton gradient

A

conserved

34
Q

What is chemiosmotic theory

A

free energy liberated by redox reactions is used by ETC to pump proteins, moving H+ from matrix to intermembrane space
- energy is stored as an electrochemical gradient
protons flow back into the matrix passively down its concentration gradient through the proton pore of ATP synthase enzyme

35
Q

The energy of electrochemical gradient is released as is used for the generation of ATP by the ________ _________________ enzyme

A

ATP synthase

36
Q

ETC and ATP synthase are _____________

A

coupled

37
Q

Chemiosmotic theory readily explains the ______________ between ETC and ATP synthase

A

coupling

38
Q

If ETC is blocked, can ATP synthase function?

A

no
and vice versa

39
Q

___________ _________________ is an obligatory part of the catalytic cycle

A

proton translocation

40
Q

How does the ETC/ATP synthase system become uncoupled

A

if the integrity of the inner mitochondrial membrane is disrupted, the proton gradient is eliminated
- ETC continues, but ATP synthase stops
*no longer coupled

41
Q

What is an example of a chemical that acts as an uncoupler

A

dinitrophenol (DNP)

42
Q

When DNP is added to the cell, what continues and what stops

A

ETC continues
ATP synthase stops

43
Q

What is the mechanism of 2,4 DNP

A
  • the DNP- picks up a proton to form DNPH
  • releases the H+ in the matrix forming DNP-
  • DNP- crosses back into intermembrane space and negative charge is delocalized over aromatic ring; structure is hydrophobic
  • proton gradient is collapsed
  • since energy is not conserved by ATP formation, it dissipates as heat

Bioc 2580 (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions