Dr Johnson - Done Flashcards
(117 cards)
1
Q
What is the meaning of anabolism?
A
the non-spontaneous production of a molecule
2
Q
What is the meaning of catabolism?
A
the spontaneous break down of a molecule
3
Q
what is the meaning of the term redox?
A
the simultaneous oxidation and reduction
4
Q
What enzyme catalyses the production of Glucose-6-Phosphate?
A
hexokinase
5
Q
What substrate is added with glucose in step 1 of glycolysis?
A
ATP
6
Q
what product is formed in step 2 of glycolysis?
A
fructose-6-phosphate
7
Q
what enzyme catalyses the production of fructose-6-phosphate?
A
phosphoglucose isomerase
8
Q
what is produced in step 3 of glycolysis?
A
fructose-1,6-bisphosphate
9
Q
what substrate is added in step 3 of glycolysis?
A
ATP
10
Q
what enzyme catalyses the production of fructose-1,6-bisphosphate?
A
phosphofructokinase
11
Q
what is produced from fructose-1,6-bisphosphate in step 4 of glycolysis?
A
GADP and DHAP
12
Q
What catalyses the splitting of fructose-1,6-bisphosphate?
A
aldolase
13
Q
What is produced from the GADP produced in steps 4/5 of glycolysis?
A
1,3-biphosphoglycerate
14
Q
What is the first energy yielding reaction in glycolysis and how is the energy stored?
A
Step 6, production of 1,3-biphosphoglycerate, NADH/H+
15
Q
Why is a phosphate added to GADP to form 1,3-biphosphoglycerate?
A
To increase the phosphoryl transfer potential
16
Q
What is catalysed the production of 3-phosphoglcyerate?
A
phosphoglycerate kinase
17
Q
How is ATP produced in step 6 of glycolysis?
A
substrate level phosphorylation
18
Q
what is produced from 1,3-biphosphoglycerate in glycolysis?
A
3-phosphoglcyerate and ATP
19
Q
What is produced from 3-phosphoglycerate in step 8 of glycolysis?
A
2-phosphoglcyerate
20
Q
What enzyme catalyses the production of 2-phosphoglycerate
A
phosphoglycerate mutase
21
Q
Why is 3-phosphoglycerate converted to 2-phosphoglycerate?
A
Increases phosphoryl transfer potential
22
Q
What is 2-phosphoglycerate broken down into in glycolysis?
A
Phosphophenolpyruvate and water
23
Q
What catalyses the production of phosphophenolpyrulvte?
A
enolase
24
Q
why is phosphophenolpyruvate produced in step 9 of glycolysis?
A
Increases phosphoryl transfer potential
25
What is the final step of glycolysis?
Production of Pyrucate and ATP from Phosphophenolpyruvate
26
What enzyme catalyses the final step of glycolysis?
Pyruvate kinase
27
Why do cancer cells acidify the surrounding environment?
damages cells around it resulting in tumour invasion
28
why do cancer cells grow without oxygen?
the blood vessels develop slower meaning their growth is not restricted?
29
How can the Warburg Effect be used to visualise cancer cells?
FDG is a glucose analogue so is brought to highly respiring cells
30
What is the end product of fermentation in the muscle cells?
2 lactate molecules per glucose
31
What is the end product of fermentation in yeast cells?
ethanol and CO2
32
when does fermentation take place?
when O2 is not available as the terminal electron acceptor
33
What is the main advantage of complexing a group of enzymes?
prevents side reactions
minimises distance
increase substrate channeling
34
What is does pyruvate react with in step one of the link reaction?
TTP to form hydroxyethyl TTP and CO2
35
What does hydroxyethyl TTP bind to in the second step of the link reaction?
Lipoamide to form Acetyl-dihydrolipoamide
36
In step 2 what is formed from Acetyl-dihydrolipoamide?
forms reduced lipoamide and acetyl CoA
37
what electron carrier is directly reduced by the reduced lipoamide molecule?
FADH to FADH2
38
What is the final electron acceptor for the link reaction?
NAD+ to NADH/H+
39
Why does fatty acid oxidation result in more energy/more ATP being produced?
Fatty acids are more reduced and therefore can be oxidised more
40
What are the products made in Fatty acid oxidation?
CoA, FADH2, NADH/H+
41
What type substrates join in step 1 if the CAC?
Oxaloacetate and Acetyl CoA
42
What catalyses the formation of citrate in the CAC?
Citrate synthase
43
What is produced in step 2 of the CAC?
isocitrate
44
What catalyses the production of isocitarte from citrate?
Aconitase
45
What occurs in the reaction to form isocitarate
Water is removed and then added back again
46
What is made after isocitrate in the CAC?
alpha-ketoglutarate
47
What molecules are produced along with alpha-ketoglutarate?
NADH/H+ and CO2
48
What enzyme catalyses the production of alpha-ketoglutarate?
Isocitrate dehydrogenase
49
What compound is added to alpha ketoglutarate to form succinyl CoA?
CoA
50
What compounds are made along with succinyl CoA?
NADH/H+ and CO2
51
What enzyme catalyses the production of succinyl CoA?
oxoglutarate dehydrogenase
52
Why is the production of succinyl CoA favourable?
It is an oxidation reaction
53
What does Succinyl CoA react with to form Succinate?
ADP, H2O and Pi
54
What by products are made by Succinate is formed?
ATP and CoA
55
What enzyme catalyses the production of succinate?
Succinyl CoA synthase
56
succinate combines with what molecules to produce fumurate and a by-product?
FAD
57
what enzyme catalyses the production of fumurate from succinate?
succinate dehydrogenase
58
Why is FADH2 produced when fumurate is made form succinate and not NADH/H+?
The energy released is not enough to couple the reduction of NAD
59
what is added to fumurate to form malate?
H2O
60
what enzyme catalyses the production of malate?
fumurase
61
what is the final step in the CAC?
Malate +NAD+ -> oxaloacetate +NADH/H+
62
what enzyme catalyses the production of oxaloacetate?
malate dehydrogenase
63
What was the main indicator that the CAC was in fact a cycle?
Many of the substrates are poisons
64
What is the role of KOH in the Warburg manometer?
absorbs CO2
65
What happens to the pressure in the flask of the Warburg Manometer as respiration takes place?
It increases
66
Which molecule is oxidised first in the G3P shuttle?
NADH/H+
67
What is the final electron acceptor in the G3P shuttle?
Ubiquinone
68
What is the aim of the G3P shuttle?
allows high rate of oxidative phosphorylation as cytoplasmic NAD+ is made
69
What is the aim of the Malate-Asparatate shuttle?
Produce NADH/H+ in the mitochondrial matrix
70
How could you describe the protein channels used in the Malate-Aspartate shuttle?
Antiports
71
What does malate move into the matrix in return for?
alpha-ketoglutarate
72
What does aspirate move into the cytosol in exchange for?
glutamate
73
What is the name of the inner most region of the mitochondria?
matrix
74
What is the name of the infolding membrane structures in the mitochondria?
cristae
75
What gradient is formed across the mitochondrial inner membrane?
Proton gradient
76
Why is the proton gradient produced in the mitochondria?
to allow the production of ATP
77
What is the best way to describe the electron transport chain?
downhill flow of electrons in energetically favourable redox reactions
78
If an electron potential is more negative, what does this mean about the substance?
it is more likely to donate electrons
79
if an electron potential is more positive. what does this mean about the substance?
It is more likely to accept electrons
80
What concentration should the compounds be in when measuring redox potentials?
Equimolar, equal parts of reduced and oxidised
81
For a standard redox potential, what are the conditions in the Hydrogen half cell?
1 atm H2, 1M H+
82
Why do we sometimes change the concentration in the hydrogen half cell when measuring redox potentials? What are the conditions changed to?
10^-7 M H+, physiological pH of the cell (pH=7)
83
What is the function of the salt bridge when measuring redox potentials?
To allow ions to flow neutralising difference in charge
84
What is the equation for free energy in terms of redox potential?
ΔG ̊= -nFΔE0
85
In the equation for free energy in terms of redox potential, what does n stand for?
number of electrons
86
In the equation free energy in terms of redox potential, what does F stand for?
Faraday constant
87
Why is aerobic respiration only 54% efficient?
energy is lost through heat
88
What classifies a protein as a flavoprotein?
uses FAD/FADH2 as a cofactor
89
Do flavoproteins allow more or less H+ to be pumped into the inner membrane space?
fewer
90
What complex do flavoprotein bypass?
Complex I
91
What molecule is reduced by Flavoproteins?
Ubiquinone
92
Which complex uses Flavin mononcleotide as a cofactor?
Complex I
93
Where does Complex I gain the 2 electrons from in the ETC?
oxidation of NADH/H+ to NAD+
94
How many protons are removed from the matrix by Complex I in the ETC
4 are directly pumped
| 2 are taken up to reduce UQ
95
What molecules are used internally in complex I of the ETC to transport electrons?
FMN
| Iron-sulfur complexes
96
Which complex reoxidises the UQH2 produced by Complex I in the ETC?
Complex III
97
How many protons are moved by Complex III of the ETC?
0 are directly pumped
| 4 are moved due to oxidation of 2 UQH2 molecules
98
What molecules are reduced by the electrons produced by Complex III?
2 Cytochrome C molecules
| 1 Ubiquinone molecule
99
How many protons are removed from the matrix by Complex III, and what are they used for?
2, they reduce UQ
100
What complexes are used to channel electrons internally in Complex III?
Iron sulfur complexes
| Haem groups
101
What is the enzymatic name of complex II in the ETC?
succinate dehydrogenase
102
What is produced when fumurate is formed from succinate by Complex II in the ETC?
2 FADH2
103
What complexes are used to transport electrons in Complex II of the ETC?
Iron sulfur complexes and Haem groups
104
What molecule does Complex IV of the ETC oxidise?
cytochrome c
105
What groups transfer electron in Complex IV of the ETC?
Haem
106
What is the fate of the electrons from the oxidised Cytochrome C in Complex IV of the ETC?
join with 2H+ from matrix and 1/2 O2 to form water
107
Where does the energy come from in Complex IV of the ETC to allow direct pumping of 2H+?
Formation of water
108
Who developed the chemiosomotic theory?
Mitchell
109
What was the original hypothesis for the production of ATP before chemiosomsis?
A high energy intermediate
110
What proton pump molecule was used to show chemiosomotic theory?
Bacteriorhodopsin
111
How did Mitchell show that the proton gradient was needed for ATP production?
He put an uncoupler in to allow H+ movement and prevent the gradient from building up
112
How does ATP synthase provide energy from the proton gradient present across the membrane?
protons with potential energy bind to the rotating ring structure allowing the transfer to mechanical/kinetic energy
113
Why does the F1 head of ATP synthase change conformation?
The stalk is connected to the head and spins changing the confirmation of the Beta domains
114
What is the O conformation of the Beta domain of ATP synthase?
change over between ATP release and ADP+Pi binding
115
What is the L conformation of the Beta domain of ATP synthase?
production of ATP
116
What is the T conformation of the Beta domain of ATP synthase?
ATP remains bound
117
What is the equation for calculating the free energy using the membrane potential and PMF?
```
Δp = Δψ - 2.3 RT/F ΔpH
ΔG = -nFΔp
```
