1
Q
What entered citric acid cycle cycle and what are the products
A
Acetyl co a is entrance molecule
Makes CO2 and H20, cycle produces NADH and FADH2, fatty acids
2
Q
Pyruvate to acetyl co a , what is the complex called
A
Pyruvate dehydrogenase complex , oxidative decarboxlyatin
3
Q
Is conversion to acetyl co a reversible and energetically favourable
A
Irreversible
Energetically favourable
4
Q
Overall reaction of pyruvate dehydrogenase complex
A
Pyruvate
CoA
NAD+
To
Acetyl-CoA
Carbon dioxide
NADH
Hydrogen
5
Q
What molecules can be used to make acetyl-CoA 4?
A
Fatty acids
Ketogenic amino acids
Ketones
Alcohol
6
Q
How do fatty acids convert to acetyl coA
A
Shuttle acyl group from systolic co-A – SH to mitochondria coA-SH via carnitine
7
Q
How do ketogenic amino acids become acetyl co-AA
A
Transaminate to lose nitrogen convert the carbon skeleton into keto body, which is then converted into acetyl coA
8
Q
How do ketones convert to acetyl-CoA
A
Reverse ketone body formation
9
Q
How do alcohols become a acetyl-CoA?
A
Alcohol dehydrogenase and acetalaldehyde dehydrogenase convert alcohol into that
10
Q
What are the 3 core enzymes in PDH
A
Pyruvate dehydrogenase
Dihydrolipoyl transacetylase
Dihydolipoyl dehydrogranase
11
Q
What does these 3 enzymes do for PDH
Pyruvate dehydrogenase
Dihydrolipoyl transacetylase
Dihydolipoyl dehydrogranase
A
- USES TPP to remove one carbon from pyruvate to release CO2
- Uses lipoic acid and CoA, transfers two carbon acetyl group to CoA to make it acetyl CoA
- Uses FAD and NAD+ . Regenerates oxidised lipoic acid and produces NADH
12
Q
Why does citric acid happen aerobcially only even without oxygen
A
Because NADH and FADH 2 will accurate if oxygen is not aaviable and inhibit cycle
13
Q
In ketogenic amino acids to convert to acetyl co A , carbon atoms that enter metabolism as acetyl can or cannot be used to make glucose
A
They cannot
14
Q
Citric acid cycle takes place where
A
Mitochondrial complex
15
Q
Main purpose of citric acid cycle
- intermediate bonding to what
- which two high energy carriers
- which form of energy
A
Oxidise car bonds in the intermediates to CO2 and generate NADH and FADH 2
GTP
16
Q
GTP made in citric cycle can be converted into what
And what phsoprylation is it
A
ATP
Substrate level phosphorylation
17
Q
2 carbon molecule that enters citric acid cycle is
A
Acetyl coa
18
Q
What is the 4 carbon molecule that accepts acetyl co a in citric acid cycle
A
Oxaloacetate
19
Q
Are carbons oxidised or reduced through citric acid cycle
A
Oxidised
20
Q
What turns oxaloacetate into citrate
A
Citrate synthase
21
Q
Citrate synthase his regulated by what feedback
And form what molecules
A
Negative feedback
ATP, NADH , succinyl coa, citrate
22
Q
What is Citrate synthase type of reaction with oxaloacetate to make citrate
A
Condensation
23
Q
Carbon is committed in which step of citric acid cycle
A
After citrate synthase combines with oxaloacetate to make citrate
24
Q
What does citrate become next in the citric acid cycle and using what enzyme
A
Aconitase isomerizes citrate to isocitrate
25
When citrate becomes isocitrate, what form of aconitate does this
Cis or trans
Cis
26
What is the rate limiting step in citric acid cycle
When isocitrate becomes ketoglutarate using isocitrate dehydrogenase
27
What does isocitrate dehydrogenase generate
Co2 and NADH
28
what inhibits isocitrate dehydrogenase
ATP and NADH
29
What activates isocitrate dehydrogenase
ADP and NAD+
30
Next step after isocitrate citric acid cycle
Isocitrate + isocitrate dehydrogenase -> Ketoglutarate
31
What happens after ketoglutarate
ketoglutarate -> ketoglutarate dehydrogenase -> Succinyl CoA
32
Where are the 1st and 2nd points where NADH and CO2 are generated in the citric cycle
Isocitrate dehydrogenase
Ketoglutarate dehydrogenase
33
What is generalsd with ketoglutaratetarate Deyydrogenase
Co2 and NADH
34
What inhibits ketoglutarateutarate dehydrogenasegenae compelx
Atp
nadh
Successiveyl coa
35
What activates (2) ketoglutarate dehydrogenase
ADP and CALCIUM
36
What thing is generated with succinyl co a synthetase
One GTP
37
What happens after succinyl co a in citric cycle
Succinyl co A. + succinyl co A synthetase -> Succinate
38
Which step in citric cycle is substrate level phosphorylation
When succinyl co a turns into succinate
39
How does succinate become next step in citric acid cycle
succinate plus succinate dehydrogenase becomes fumarate
40
What do the electrons removed from succinate reduce what
Fad to FADH 2
41
Only step in citric cycle that makes FADH2
Succinate dehydrogenase
42
Where do FADH2 made in citric acid cycle go
Goes into complex II for ETC
43
What is next step after fumarate how it occurs
Fumarate plus fumarase leads to malate
44
What happens to malate what doles it become after in citric acid cycle
Malate plus malate dehydrogenase becomes oxaloacetate
45
What is released in malate dehydrogenase
NAD becomes NADH
46
Pyruvate dehydrogenase complex equation
3 reactants, 4 products
Pyruvate+ CoA-SH+NAD+ -> acetyl coA + NADH + Co2 +H+
47
Citric acid cycle equation
6 reactants
6 products
Acetyl coa + 3NAD+ FAD++GDP+Pi +H2O -> CO2 + CoA-SH + NADH +H+ FADH2+GTP
48
How many ATP per pyruvate are made
12.5
49
How many ATP made per glucose
25
50
Glycolysis yields how many ATP and NADH
2atp, 2nadh
51
How many NADH made in ATP production
How many ATP is that equivalent to
4 NADH , 10 ATP
52
Each NADH is worth how many atp
2.5
53
How many FADH2 made in ATP production
How many ATP is that equivalent to
1.5 atp , 1 FADH 2
54
How many FADH2 equal to atp
1.5
55
How many GTP equal to atp
1 to 1 ratio
56
How many GTP created in citric acid cycle
1 GTP , 1 atp
57
Glycolysis contributes about 7 atp per glucose, aside from 1 GTP, the atp that is produced is made in which cycle
In ETC not in citric acid cycle
58
What does pyruvate dehydrogenase kinase do
Phosphrylates pyruvate dehydrogenase and turns it off
59
What is pyruvate dehydrogenase kinase activated by (2)
Why
Acetyl coa and NADH
It’s already made so it can turn off
60
What does pyruvate dehydrogenase phosphatase do
Removes phosphate group and activates pyruvate dehydrogenase
61
What activates pyruvate dehydrogenase phosphatase (2)
Insulin
Calcium
62
There are 3 control points in citric cycle what are they
Citrate synthase
Isocitrate dehydrogenase
Ketoglutarate dehydrogenase complex
63
Last step of aerobic respiration is
electron transport chain
64
What is the purpose of ETC
And through what process
Use the electrons from NADH and FADH2 to drive ATP production through oxidative phosrylation phosphorylation
65
Where is etc
Inner mitochondrial membrane
66
Why do electrons move through the membrane bound complexes in order of increasing reduction potential
What is the purpose, what is this electron transfer used for
What 2 gradients are created
It releases energy this way
And energy is used to pump proton into intermembrane space create electrical gradient and concentration gradient to make electrochemical gradient
67
What force is created in ETC
Proton motive force
68
When is ATP synthesized in ETC, like what happens for it to be synthesized in terms of proton movement
What is this process called
It is when protons flow back into the matrix through ATP synthase through oxidative phosphorylation q
69
What is the final electron acceptor in ETC
Oxygen
70
Oxygen is reduced to what in the end of ETC
Water
71
Formation of ATP
Electron transport
Exergonic or endergonic
Formation of atp is endergonic
Electron transport is exergonic
72
Complex I is also called what in ETC
NADH CoQ oxidoreductase
73
Complex II is called what in ETC
Succinate Co2 oxidoreductase
74
What is complex I for in ETC
Primary entry point for electrons carried by NADH from glycolysis , pyruvate dehydrogenase reaction and citric acid
75
What are the reactants (3) and products (2) of complex I in ETC
Reactant : NADH, H+. COQ
Products: NAD+, CoQH2 (ubiquinone)
76
What is complex II also called in ETC
Succinate CoQ oxideoreductase
77
What does complex II do for ETC
Passing electrons from succinate to CoQ to form CoQH2
78
What is the net equation for complex II
Succinate + COQ + H = fumarate +COQH2
79
Where do the electrons from FADH 2 go in complex II in etc
To Coenzyme Q
80
Does complex I or II pump protons across mitochondrial membrane
Why
Just I not II
FADH2 less energy
81
What is complex III also called
CoQ cytochrome C oxidoreductase
82
What does Complex III do in ETC
ELECTRONS from complex I and III from the CoQH2 to heme to form cytochrome c
83
What happens in complex III to its reactants
Also what happens to additional protons
CoQH2 becomes back to its CoQ original form
Cytochrome c becomes reduced and additional protons are pushed out matrices
84
What is complex IV also called
Cytochrome c oxidase
85
What doles complex IV do to ETC
Electrons from cytochrome c gets moved to oxygen to form water
86
Which complex in ETC pumps protons into intermembrane space
I
III
IV
87
Which complex in ETC acquires electrons from NADH
I
88
Which complex in ETC acquires electrons from FADH2
II
89
Which complex in ETC has highest reduction potential
Is there a trend across all complexes
IV
Because reduction potential increases along ETC
90
Based on its needs, which of the two shuttle mechanisms is cardiac muscle most likely to use and why
Malate aspartate shuttle
More efficient for highly aerobic organ to maximize atp yield
91
What pumps hydrogen in ETC
ATP synthetase
92
When hydrogens get moved back into mitochondria using ATP synthase , what is the process called
Oxidative phosphorylation
93
What are the 2 nadh shuttles in etc
Glycerol 3 phosphate shuttle
Malate aspartate shuttle
94
Why are there nadh shuttles
Cytosolic NADH
Glycolysis
Movement
To transport electrons from cytosolic NADH which are produced during glycolysis to cross the imperameable inner mitochondrial membrane to ETC
95
How doles glycerol 3 phosphate shuttle work (NADH SHUTTEL) in etc
Is it high atp yield and why
Cytosolic NADH transfers electrons to DHAP, and it reduces it into G3P. These electrons enter ETC as FADH2 at complex II.
Because it bypasses complex I, this shuttle produces less atp per cytosolic NADH q
96
How does malate aspartate cshuttle work in etc (NADH shuttle)
Is it high or low atp yield and why
Cytosolic nadh reduces oxaloacetate into malate which crosses into the mitochondrial matrix .
Once it enters it oxidizes back to oxaloacetate to regenerate NADH.
FULL atp yield is preserved as the enter through complex I still
97
_______ force is the _______ gradient generated by the _________ across ____________
PMF
Electrochemical
ETC
Inner mitochondrial membrane
98
Does matrix or intermembrane space have higher concentration of protons during etc
Intermembrane space has higher than matrix
99
The gradients in oxidative phosorylation can be used to form ________ via ___________
ATP
Chemiosmotic coupling
100
What is the enzyme responsible for generating atp form ADP and inorgani phosphospahte in Etc
ATP synthase
101
Is intermembrane space of matrix positive or negative in terms of electro charge
Intermembrane is positive
Matrix is negative
Stores potential energy
102
What is chemiosmotic coupling
Idea that movement of ions down electrochemical gradients is directly coupled to atp synthesis
103
There are two parts of atp syntahse
F0 and F1
104
What does F0 portion do in atp synthase
What is it essentially
It is an ion channel
Allowing proteins to flow down the gradien from the intermembrane space to the matrix
105
What does F1 portion of atp synthase do
Uses energy released by gradient in F0 portion to phosphorylate ADP to ATP
106
Ph drop in chemiosmotic coupling
Is that a rise or drop in proton concentration
Rise
107
Total atp per glucose is
30-32
108
Key regulators of oxidative phosprylation (2)
Oxygen
ADP
109
What is the only product from pyruvate dehydrogenase other than acetyl co a
NADH
110
Difference between ETC and oxidative phosphorylation
What links the two
Etc is a set of oxidative and reduction reactions on the inner mitochondrial matrix using intermembrane proteins and the final electron acceptor is oxygen
PMF s generated by intermembrane space when electrons are transferred
Oxidative phosphorylation is where atp is generated by harnessing this gradient and uses atp synthase for hte process.
111
Why does transferring electrons along the etc generate more ATP than direct reduction of oxygen by nadh
Splitting into different complexes creates enough energy released to create proton gradients at many locations rather than just one. The greater the proton gradients, the greater the atp generated would be. Just direction reduction of oxygen would yield less energy so inefficient electron transport
112
The coordinated efforts of both oxidative phosphorylation and citric acid cycle is called what control
Respiratory control
113
How would citric acid cycle and oxidative phosphorylation be affected by low O2
3 steps
low oxygen means less oxidative phosphorylation
That means more NADH and fadh2
Which mans citric cycle would inhibited
MCAT
flashcards
Decks in class (48)
# Cards
-
Biology Chapter 1176
-
Biology Chapter 2134
-
Biology Chapter 3131
-
Biology Chapter 495
-
Biology Chapter 5123
-
Biology Chapter 659
-
Biology Chapter 7122
-
Biology Chapter 8107
-
Biology Chapter 989
-
Biology Chapter 1070
-
Biology Chapter 1194
-
Biology Chapter 1274
-
Chemistry Chapter 151
-
Chemistry Chapter 242
-
Chemistry Chapter 354
-
Chemistry Chapter 450
-
Chemistry Chapter 531
-
Chemistry Chapter 622
-
Chemistry Chapter 756
-
Chemistry chapter 833
-
Chemistry Chapter 933
-
Chemistry Chapter 1048
-
Chemistry Chapter 1121
-
Chemistry Chapter 1253
-
Organic Chemistry 130
-
Organic Chemistry Chapter 241
-
Organic Chemistry Chapter 318
-
Organic Chemistry Chapter 454
-
Organic Chemistry Chapter 523
-
Organic Chemistry Chapter 620
-
Ogranic Chemistry Chapter 729
-
Organic chemistry chapter 839
-
Organic Chemistry Chapter 921
-
Organic Chemistry Chapter 1029
-
Organic Chemistry Chapter 1135
-
Organic Chemistry Chapter 1238
-
Biochem Chapter 194
-
Biochem Chapter 295
-
Biochem Chapter 381
-
Biochm Chapter 451
-
Biochem Chapter 571
-
Biochem Chapter 6125
-
Biochem Chapter 794
-
Biochem Chapter 875
-
Biochem Chapter 9132
-
Biochem Chapter 10113
-
Biochem Chapter 11114
-
Biochem Chapter 12107
