Brainscape's Knowledge GenomeTM

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


See full index

BIOL1008 > Cell metabolism > Flashcards

Cell metabolism Flashcards

1
Q

What are the types of metabolic pathways and explain each?

A

Anabolic: Pathways require energy and are involved in the biosynthesis of complex molecules from simpler molecules

Catabolic: Pathways release energy and involve breakdown of molecules

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

What forms can metabolic pathways be?

A
  1. linear
  2. Branched
  3. Circular
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

The me for the number of carbons 3-9 their category name and relevant examples for each?

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

How are monosaccharides classified in humans?

A

According to the number of carbons they contain in their backbone

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

How many carbon atoms dows the main monosaccharide contain?

A

4-6 carbon atoms

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

What 2 functions does the oxidative catabolism of glucose serve?

A
  1. The production of ‘free energy’ in the form of ATP
  2. The production of intermediated from glycolysis and the TCA cycle to provide material for other metabolic pathways
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Whats the definition of Oxidative metabolism?

A

a chemical process in which oxygen is used to make energy from carbohydrates, also called aerobic metabolism, aerobic respiration, and cells respiration

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

Tell me the importance of glucose

A
  1. Energy requirement of the cell
  2. material requirements of the cell

However these cannot be done at the same time

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

Whats the equation for the reaction between glucose and oxygen ?

Whats the standard free energy change for this reaction?

A

C6H12O6 + 6O2 <–> 6CO2 + 6H2O

∆Gø’ = -2834 kj/mol

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

Energy released from fuel oxidation that is not used for work is transformed into what?

A

its transformed into and released as heat

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

Whats the definition of ∆Gø ?

A

This is the change in Gibbs free energy at pH 0 (1 M [H+]) under standard conditions

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

Whats the definition of ∆Gø’ ?

A

The change in Gibbs free energy at pH 7.0 under standard conditions

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

What information does the ∆Gø’ provide?

A

What happens to the free energy (energy available to do work) during chemical/ biological reactions

The amount of free energy available to do work is related to the difference in energy levels between products and reactions

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

If ∆Gø’ is negative and free energy, the reaction is said to be…?

A

Exergonic

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

If ∆Gø’ is positive and free energy is absorbed, the reaction is said to be…?

A

Endergonic

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

What processes can release energy?

Give an example for each?

A
  1. mechanical work e.g. muscle contraction
  2. Transport work e.g. establishment of ionic gradients
  3. Heat generation
  4. Biochemical work e.g. energy-requiring chemical reactions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The heart is a specialist in the transport of what?

If the heart wasn’t able to do this, what would happen?

A

The heart is a specialist in the transformation of ATP chemical bond energy into mechanical work

If the heart were not able to regenerate ATP, all of its ATP would be hydrolysed in less than 1 min- absolute requirement for oxidative phosphorylation

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

Whats the equilibrium constant ?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Tell me about the magnitude of the equilibrium constant?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

whats the value of ∆Gø at equilibrium?

A

0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Whats the Van’t Hoff isotherm equation and what does each part of the equation represent?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What does the equation ∆Gø= -RT ln K allow us to predict/ estimate?

A
  1. To predict if a reaction happens spontaneously or notm if K is known
  2. To estimate if the reaction lied to the left or right, if ∆Gø is known
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

The table shows the value of Kc and ∆G

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Why is ∆Gø’ used?

A

In order to compare free energy changes for different reactions, it is necessary to express ∆G values relative to some standard state hence the use of ∆Gø’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

The relationship between the free energy of reaction at any moment in time (∆G) and the standard-state free energy of a reaction (∆Gø’) is described by what equation?

A

∆G = ∆Gø’ + RT lnQ

where Q= [Products]/ [Reactants]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

At equilibrium, ∆G=0 so what does ∆Gø’ equal?

A

∆Gø’ = -RT lnQ

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

∆G is dependent on what two parts?

A
  1. A constant term whose value depends only on the reaction taking place
  2. A variable term that depends on the concentration of reactants and products
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

if ∆G is negative, the equilibrium lies in favour of what?

A

the products

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

If ∆G is positive, the equilibrium lies in favour of what?

A

The reactants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

If ∆G is large and negative what does this mean?

If ∆G is large and positive what does this mean?

A

If ∆G is large and negative, the reaction equilibrium is essentially irreversible.

If ∆G is large and positive, the reaction will not proceed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Whats La Chatelier’s principle?

A

Any deviation from equilibrium stimulates a process that tends to restore the system to equilibrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Some metabolic reactiond are close to their equilibrium concentrationm hence if [substrate] increases, what direction does the reaction proceed?

A

To the right and more products are made

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

In energy producing and energy utilising metabolic pathways, ∆G values are additive

A

A –> B –> C –> D

∆G(A-D) = ∆G(A-B) + ∆G(B-C) + ∆G(C-D)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Any one reaction can have a positive ∆G, but if the overall ∆G is negative then what happends to the pathway?

A

It will proceed

35
Q

Couples reactions drive endergonic processes

example below…

A
36
Q

What are the characteristics of metabolic pathways?

Give an explanation of each?

A
  1. Metabolic pathways are irreversible. A highly exergonic reaction is irreversible; that is, it goes to completion. If such a reaction is part of a multistep pathway, it confers directionality on the pathway.
  2. Every metabolic pathway has a first committed step. Although most reactions in a metabolic pathway function close to equilibrium, there is generally an irreversible (exergonic) reaction early in the pathway that “commits” its product to continue down the pathway.
  3. Catabolic and anabolic pathways differ. The existence of independent interconversion routes allows independent control of the two processes.
  4. Feedback inhibition. The product of a late or last step frequently acts as an inhibitor of the first committed step. Hence, end product controls its own synthesis. All metabolic pathways are regulated.
  5. In eukaryotes, metabolic pathways occur in specific cellular locations.
  6. Metabolic pathways are controlled by switching on/off the gene for the first enzyme. If the gene to produce the first enzyme is switched off, the enzyme is not produced, and the rest of the pathway stops. Control of flux is based on the number of key enzymes and the presence of tissue specific isoenzymes and their regulation once made.
  7. Enzymes often act in groups or as multi-enzyme complexes.
37
Q

These diagram shows feedback inhibition

A
38
Q

Tell me some facts about feedback inhibition and steps…

A
39
Q

Whats the definition of 1 calorie

A

1 calorie= the heat energy required to raise 1g of H2O by 1˚c

40
Q

You can have a high or low metabolic rate but NOT a fast or slow metabolism

A
41
Q

Draw the open and cyclic forms of glucose and the % of them found in nature

A

Be aware of location of OH on the linear glucose and what side its on

42
Q

In glycolysis there are 3 irreversible steps, whats the first irreversable reaction?

A
43
Q

Name the enzyme that removes phosphate and one that adds phosphate?

A

Phosphorylase: adds a phosphate

Phosphatase: removes a phosphate

44
Q

Whats the second irreversible step of glycolysis ?

A
  • Step 2 is a coupled reaction as provides energy from ATP
  • Sequential addition of phosphate groups: AMP –> ADP –> ATP
  • Bisphosphate means 2 phosphates added to different places
45
Q

Whats the 3rd irreversible step of glycolysis ?

A

This ones ADP –> ATP rather than in the other two steps

46
Q

why are those steps in glycolysis irreversible?

A

because of their large, negative ∆G

47
Q

Whats a cofactor?

A

A non-protein component of enzymes

48
Q

Name the divisions of cofactors?

A
49
Q

If the cofactor is organic, then what is it called?

A

A coenzyme

50
Q

What are many coenzymes derived from?

A

Vitamins

51
Q

Name 5 vitamins, their coenzyme and their function?

A
52
Q

When coenzymes are involved in catabolism of glucose what are they considered to be?

A

A co-substrate

53
Q

Whats a coenzymes role?

A

Their role is to deliver chemical groups or atoms e.g. H+, phosphate, to/from the active site

54
Q

Name the coenzyme which is involved in the transfer of protons

A

Nicotinamide adenine dinucleotide (NAD+)

55
Q

Whats the coenzyme thats involved in the transfer of phosphate groups?

A

Adenosine triphosphate (ATP)

56
Q

Draw the structure of NADH/NAD+

A
57
Q

Tell me about oxidation and reduction

A
58
Q

Write the NADH/NAD+ redox reaction

A

NAD+ + 2H+ + 2e- NADH + H+

59
Q

Give an example of redox from metabolism

A

As the NADH is oxidised, the pyruvate is reduced. This reaction occurs in your muscles under low oxygen conditions

60
Q

Give me an redox example from glycolysis

A

Phosphate is added from solution not ATP

Goes from a low energy –> high energy

61
Q

As well as being involved in the transfer of phosphate groups what does ATP/ADP + Pi play a key role in?

A

metabolism coupling together energy producing (exergonic) reactions with energy requiring (endergonic) reactions

62
Q

the equilibrium of endergonic reactions lies in favour of what?

A

the substrate- but coupling it to an exergonic reaction can shift the equilibrim in favour of product

An example of this is below…

63
Q

draw the reaction of ATP and write the direction of the endergonic/ exergonic reactions

A
64
Q

Draw the structure of ATP

A
65
Q

Draw the structure of GTP

A
66
Q

Is GTP a high energy nucleotide ?

A

yes

67
Q

Is ATP an energy transducer ?

A

yes

68
Q

does ATP store energy?

A

no

69
Q

Is ATP produced on demand or is it always made?

A

it is produced on demand by the phosphorylation of ADP and Pi

70
Q

What are the phosphate groups of ATP stabilised by?

A

resonance

71
Q

When would phosphate groups repel each other?

A

if you were to put the like-poled ends together they repel each other

72
Q

When a phosphodiester bond is cleaved, whats the energy from those bonds used for? give an example

A

Those bonds can be used to perform biochemical work, such as transferring a functional group from one molecule to another

73
Q

are phosphorylation reaction endergonic or exergonic

A

endergonic

74
Q

Why does phosphorylation need to be a coupled reaction?

A

to provide energy to make the reaction occur

75
Q

Is Dephosphorylation endergonic or exergonic

A

exergonic

76
Q

What is the value of ∆G in the oxidation of an aldehyde to a carboxylate?

What is this reaction coupled to ?

A

large and negative

This is coupled to the endergonic phosphorylation reaction and the NAD+ reduction

77
Q

What is used to form ATP?

A

The energy of oxidation is initially trapped as a high-energy phosphate (1,3- biphosphoglycerate) compound and then used to form ATP

78
Q

Is carboxylation of the methyl group an endergonic or exergonic process ?

A

endergonic

79
Q

is the De-carboxylation endergonic or exergonic ?

When a phosphate is then added is the reaction endergonic or exergonic?

A

De-carboxylation is exergonic

addition of a phosphate is endergonic

80
Q

What can GTP also act as?

A

A co-substrate

81
Q

Are oxidation reactions exergonic or endergonic ?

A

exergonic

82
Q

Energy from oxidation of NADH is used to drive what?

A

The formation of ATP

83
Q

For every 1 NADH oxidised, how many ATPs are made ?

A

3

84
Q

is there a lot of energy trapped in NADH?

A

yes

BIOL1008 (8 decks)

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