Bioenergetics Flashcards Preview

Biochemistry > Bioenergetics > Flashcards

Flashcards in Bioenergetics Deck (64)
Loading flashcards...
1
Q

A ____ Gibbs free energy suggests that the reaction proceeds spontaneously.

A

negative

2
Q

_____ determines the speed of the reaction while the free energy dictates the direction of the reaction. It does not affect the Keq.

A

enzyme (it lowers the activation energy needed)

3
Q

ATP has ____ bonds that are high in energy which contains a Gibbs free energy of -7.3kcal/mol

A

Anhydride bonds.

4
Q

NAD3+ : 3ATP :: ____: 2ATP

A

FADH2

5
Q

Niacin can be derived from this amino acid.

A

Tryptophan

6
Q

In terms of oxidizing capacity, FAD ____ NAD (greater, lesser)

A

greater

FAD is mostly involved in carbon-carbon bond reaction

7
Q

Inhibitor for ETC Complex 1

A

Pericidin a
Amytal
Rotenone
Barbiturates

8
Q

Inhibitor of complex II

A

Malonate
Carboxin
TTFA

9
Q

Inhibitor of Complex III

A

Antimycin A

Dimercaprol

10
Q

Inhibitor of complex IV

A

Cyanide
CO
Sodium azide
Hydrogen sulfide

11
Q

ATP synthase inhibitor

A

Oligomycin

12
Q

____ is the transfer and utilization of energy in biologic systems

A

bioenergetics

13
Q

____ measure of change in heat content

A

enthalpy (Joules)

14
Q

___ measure of the change in randomness or disorder

A

entropy (J/Kelvin)

15
Q

____ energy available to do work

A

free energy or Gibbs free energy

16
Q

___ refers to the delta G in standard conditions

A

Standard Free energy

17
Q

in standard free energy, the concentration of the reactants and products are ____

A

1 molar each

18
Q

___ reaction

if there is a net loss of energy

A

Exergonic

19
Q

___ reaction

if there is a net gain of energy

A

Endergonic

20
Q

What is the delta G of exergonic reactions?

A

<0

spontaneous

21
Q

endergonic reactions proceed by ___

A

coupling it to exergonic processes

22
Q

What is the standard free energy of ATP to ADP + P

A

-7300 cal/mol

23
Q

The phosphate released after hydrolysis of ATP is stabilized by

A

formation of resonance hybrid in which the 3 negative charges are shared between the 4 O atoms

24
Q

What are the compounds with a standard free energy higher than ATP?

A
  1. PEP
  2. Carbamoyl phosphate
  3. 1,3 BPG
  4. Creatine phosphate
25
Q

___ refers to the formation of ATP and a phosphorylated intermediate

A

Substrate level phosphorylation

26
Q

In substrate level phosphorylation, the phosphate group comes from ____

A

another substance with higher standard free energy

27
Q

How many high energy phosphates are formed in glycolysis via substrate level phosphorylation?

A

Two

  1. Phosphoglycerate Kinase
  2. Pyruvate kinase
28
Q

How many high energy phosphate is formed in Krebs Cycle via substrate level phosphorylation?

A

One

1, Succinyl thiokinase

29
Q

Refers to formation of ATP via chain of oxidation reaction

A

Oxidative Phosphorylation

30
Q

What is the final electron acceptor of ETC?

A

Oxygen

31
Q

Substrate level phosphorylation occur in which part of the cell

A
  1. Cytosol

2. Mitochondria

32
Q

Which part of the mitochondrion houses the mtDNA and ribosomes and enzyme

A

matrix

33
Q

___ is the final common pathway by which electrons from different fuels of the body flow to oxygen

A

ETC

34
Q

The electron transport chain generally happens in which specific part of the mitochondria?

A

inner membrane

35
Q

What are the 2 electron carriers used in the ETC

A
  1. NAD+

2. FAD

36
Q

In the ETC, NAD+ and FAD undergo ___ (oxidation/reduction)

A

REDUCTION

37
Q

These donate electrons to the specialized electron carriers in the ETC

A
  1. NADH

2. FADH2

38
Q

What electron carrier is derived from Vitamin B3?

A

NAD

39
Q

What electron carrier is derived from Vitamin B2?

A

FAD

40
Q

___ is the only non-protein component of the ETC

A

Uniquinone (CoQ)

41
Q

These components of the ETC are not fixed

A
  1. Coenzyme Q

2. Cytochrome C

42
Q

[ETC: name that complex]

NADH dehydrogenase

A

Complex I

43
Q

[ETC: name that complex]

Succinate dehydrogenase

A

Complex II

44
Q

[ETC: name that complex]

Cyt b-c1 complex

A

Complex III

45
Q

[ETC: name that complex]

Cyt C oxidase

A

Complex IV

46
Q

In the complex II, succinate deydrogenase converts succinate to what compound?

A

Fumarate

47
Q

Coenzyme Q received electrons from what complexes?

A

Complex I and II

48
Q

___ hypothesis explaining how free energy is generated by the transport of electrons by the ETC

A

Mitchell Hypothesis

49
Q

What drives OXIDATIVE phosphorylation?

A

Increase of H+ and electrical gradients

50
Q

Complex V refers to __

A

ATP synthase

51
Q

What are the effects of ETC inhibitors?

A
  1. Decrease oxygen consumption
  2. Increase intracellular NADH/NAD+ and FADH2/FADH ratios
  3. Decrease ATP
52
Q

What are Complex I inhibitors?

A
  1. Barbiturates
  2. Amytal
  3. RotenONE
  4. Piercidin A
53
Q

What are your complex II inhibitors?

A
  1. Malonate
  2. Carboxin
  3. TTFA
54
Q

What are complex III inhibitors?

A
  1. Antimycin A

2. Dimercaprol

55
Q

What are complex IV oxidase?

A
  1. Cyanide
  2. CO
  3. Azide sodium (sodium Azide)
  4. Hydrogen sulfide
56
Q

Inhibitors of these ETC complexes prevent electrons from reaching oxygen

A

Complex III and IV

57
Q

__ increase the permeability of the inner mitochondrial membrane to protons in the ETC

A

uncouplers

58
Q

What are the effects of electron transport chain uncouplers?

A
  1. Increase oxygen consumption
  2. Decreased NADH/NAD+ and FADH2/FADH ratio
  3. decrease ATP synthesis
59
Q

What is a natural ETC uncoupler?

A

Thermogenin (brown fat)

60
Q

Examples of synthetic ETC uncouplers

A
  1. 2,4 dinitrophenol

2. aspirin

61
Q

What drug blocks the F0 subunit of the ATP synthase

A

Oligomycin

62
Q

___ inhibits oxidative phosphorylation by inhibiting the transporter of ADP into and ATP out of the mitochondrion

A

Atracytloside

63
Q

What compounds partially reduce the unstable by products formed by ETC?

A

Unstable products = ROS

  1. Superoxide
  2. Hydrogen peroxide
  3. Hydroxyl radical
64
Q

What enzymes act as defenses against ROS?

A
  1. Catalase
  2. Peroxidase
  3. Superoxide dismutase