TCA

Question 1

Aerobic pathways/ respiration

Answer 1

TCA

ETC / Oxidative Phosphorylation

Question 2

Reactions that take place in TCA

Answer 2

decarboxylation
redox
hydrogenation/dehydrogenation
isomerization

Question 3

TCA coenzymes

Answer 3

NAD and FAD

Question 4

vitamin derivative of NAD

Answer 4

niacin or nicotinamide

Question 5

vitamin derivative of FAD

Answer 5

riboflavin

Question 6

vitamin derivative of CoA

Answer 6

pantothenic acid

Question 7

Vitamin B derivatives of NAD, FAD, and CoA are

Answer 7

fat soluble

Question 8

starting material for citric acid cycle

Answer 8

Acetyl CoA

Question 9

converts pyruvate to Acetyl-CoA

Answer 9

pyruvate dehydrogenase complex

Question 10

1 turn of TCA yields:

Answer 10

1 ATP
3 NADH
1 FADH2

Question 11

Step 1

Answer 11

Acetyle CoA + Oxaloacetate ——> Citrate

Citrate synthase

Question 12

reactions occuring in step 1

Answer 12

condensation

dehydration synthesis

Question 13

number of carbons in oxaloacetate and Acetyle CoA

Answer 13

4C - Oxaloacetate

2C - Acetyl CoA

Question 14

6C molecule product of step 1

Answer 14

Citrate

Question 15

by product of step 1

Answer 15

CoA-SH

Question 16

Step 2

Answer 16

Citrate —–> cis - Aconitate ——> Isocitrate
(reversible)
aconitase

Question 17

tertiary alcohol which is not oxidizable

Answer 17

Citrate

Question 18

secondary alcohol that can be oxidized

Answer 18

Isocitrate

Question 19

Reactions in Step 2

Answer 19

Isomerization
dehydration
hydration

Question 20

Step 3

Answer 20

Isocitrate ——–> Oxalosuccinase ———> a-ketoglutarate
isocitrate dehydrogenase

Question 21

Reactions occuring in Step 3

Answer 21

Redox

decarboxylation

Question 22

byproducts of Step 3

Answer 22

NADH

CO2

Question 23

oxidizing agent in step 3

Answer 23

NAD+

Question 24

ketone

formed when isocitrate is oxidized leading to reduction of NAD+ and decarboxylated

Answer 24

a-ketoglutarate

Question 25

Step 4

Answer 25

a-ketoglutarate ———-> succinyl-CoA + CO2

a-ketoglutarate dehydrogenase complex

Question 26

byproduct of Step 4

Answer 26

NADH

Question 27

coenzyme added in step 4

Answer 27

CoA

Question 28

Reactions in Step 4

Answer 28

Oxidation

Question 29

bond formed by CoA

Answer 29

thioester bond

Question 30

ketone

Answer 30

succinyl-CoA

Question 31

Step 5

Answer 31

succinyl-CoA ———> succinate
(reversible)
succinyl-CoA synthetase

Question 32

byproducts of Step 5

Answer 32

CoA-SH

GTP

Question 33

Reactions in Step 5

Answer 33

thioester bond cleavage in succinyl-CoA

phosphorylation of GDP

Question 34

Step 6

Answer 34

succinate ———> Fumarate (reversible)

succinate dehydrogenase

Question 35

Reactions in step 6

Answer 35

Oxidation

-2H atoms

Question 36

byproduct of step 6

Answer 36

FADH2

Question 37

alkane

Answer 37

succinate

Question 38

alkene

trans double bond

Answer 38

Fumarate

Question 39

Step 7

Answer 39

Fumarate ———> Carbanion transition state ——> L-malate
fumarase

Question 40

added to reaction in step 7

Answer 40

OH-

H+

Question 41

cis double bond; toxic

Answer 41

L-malate

Question 42

Step 8

Answer 42

L-Malate ———> Oxaloacetate

L-malate dehydrogenase

Question 43

byproduct of Step 8

Answer 43

NADH

H+

Question 44

oxidizing agent of Step 8

Answer 44

NAD

Question 45

Regulation of TCA

Answer 45

Citrate
Citrate synthase
Isocitrate dehydrogenase

Question 46

regulatory effector of the pathway

Answer 46

citrate

Question 47

inhibited by ATP, NADH, succinyl CoA

Answer 47

citrate synthase

Question 48

key regulatory enzyme

Answer 48

Isocitrate dehydrogenase

Question 49

inhibits citrate synthase

Answer 49

ATP
NADH
succinyl-CoA

Question 50

inhibits isocitrate dehydrogenase

Answer 50

ATP

NADH

Question 51

stimulates isocitrate dehydrogenase

Answer 51

Ca2+
ADP
AMP

Question 52

Fates of Acetyl CoA

Answer 52

TCA
Ketone bodies
Steroids or fatty acids

Question 53

Redox reactions

Answer 53

3
4
6
8

Question 54

Decarboxylation reactions

Answer 54

3,4

Question 55

Dehydration reaction

Answer 55

2

Question 56

Hydration reactions

Answer 56

2,7

Question 57

Steps that produce NADH

Answer 57

3,8,4

Question 58

Step the produces GTP

Answer 58

5

Question 59

Step that produces FADH

Answer 59

6

Question 60

Steps that release CoA-SH

Answer 60

1,5

Question 61

Step that uses CoA-SH

Answer 61

4

Question 62

Sources of pyruvate

Answer 62

Glucose (via glycolysis)
Lactic Acid (via oxidation)
Alanine (via deamination)
Glucogenic AA (via catabolism)

Question 63

Fate of pyruvate

Answer 63

gluconeogenesis
conversion to lactate (via reduction)
conversion to OAA (via carboxylation)
conversion to ACoA (via oxidative decarboxylation)
synthesis of alanine (via transamination)

Question 64

central step for linking glycolysis with TCA

Answer 64

Oxidation of pyruvate to Acetyl CoA

Question 65

3C unit
reaction:
compartment:
site:
nature:
enzyme:
ATP produced:

Answer 65

pyruvate
oxidative decarboxylation
mitochondria
all cells and tissues
catabolic
PDH
3 ATP per pyruvate

Question 66

a cluster of 3 enzymes that requires 5 cofactors

Answer 66

PDH

Question 67

Enzyme 1

Answer 67

Pyruvate dehydrogenase

Question 68

Enzyme 2

Answer 68

Dihydro Lipoyl Trans Acetylase

Question 69

Enzyme 3

Answer 69

Dihydro Lipoyl Dehydrogenase

Question 70

Coenzymes in PDH complex

Answer 70

TPP - thiamine pyrophosphate
CoA
FAD
NAD
Lipoamide

Question 71

aka thioctic acid
has 2 S atoms and C atoms
can accept or donate H atoms

Answer 71

lipoate/lipoic acid

Question 72

decarboxylates pyruvate to make the enolic form of AcCoA

Answer 72

E1/ pyruvate dehydrogenase

Question 73

cofactors in E1

Answer 73

TPP

Vit B1

Question 74

turns this into regular AcCoA

Answer 74

E2

Question 75

cofactors of E2

Answer 75

CoA

Lipoic acid

Question 76

reconstructs lipoic acid

Answer 76

E2
FAD
Vit B2

Question 77

Oxidizes FADH back to FAD

Answer 77

E3
NAD
Vit B3

Question 78

nature of Acetyl CoA

Answer 78

amphibolic

Question 79

rate limiting enzymes of TCA

Answer 79

Citrate synthase
Isocitrate DH
a-KG DH

Question 80

total number of ATPs formed

Answer 80

38

Question 81

Common metabolic pathway

Answer 81

3,4

Question 82

Fuel for TCA

Answer 82

AcCoA

Question 83

Oxidizing agent for formation of C-O double bond

Answer 83

NAD

Question 84

Oxidizing agent for C-C double bond

Answer 84

FAD

Question 85

Two C enter as-

Answer 85

Acetyl group of AcCoA

Question 86

Two C leave as

Answer 86

CO2

Question 87

4 Vitamins needed in TCA

Answer 87

Riboflavin
Nicotinamide
Pantothenic A
Thiamine

Question 88

Catalyst of TCA
Regenerated
Can condense with many AcCoA

Answer 88

OAA

Question 89

ATP produced in glycolysis

Answer 89

8

Question 90

ATP produced in Oxidative decarboxylation of pyruvic acid

Answer 90

6

Question 91

ATP produced in krebs

Answer 91

24

Question 92

Methyl carbon of acetyl group is joined to carbonyl group (C2) of OAA

Answer 92

1

Question 93

Hydroxyl group of citrate is exchanged for an H atom on an adjacent carbon

Answer 93

2

Question 94

Isocitrate is oxidized by hydride transfer to NAD

Decarboxylation is facilitated by electron withrawal by bound Mn2+

Answer 94

3

Question 95

H atom must be removed from SH Group for CoA to form high energy thioester bond

Identical to PDH reaction

Answer 95

4

Question 96

Succinyl CoA’s thioester bond is hydrolyzed forming succinate which generates GTP

Answer 96

5

Question 97

Succinate formed from succinyl CoA is oxidized by FAD to fumarate

Answer 97

6

Question 98

Fumarate is hydrated to form L-malate

Answer 98

7

Question 99

Oxidation of L-malate to oxaloacetate

Answer 99

8