Glucose Metabolism: Regulation And Important Steps.

Front 1

What is the rate limiting step in glycolysis?

Back 1

The conversion of fructose-6-phosphate to fructose-1,6-bisphosphate catalyzed by phosphofructokinase 1.

Front 2

What enzyme catalyzes the production of fructose-1,6-bisphosphate?

Back 2

Phosphofructokinase 1.

Front 3

What enzyme catalyzes the first step in glycolysis?

Back 3

Hexokinase.

Front 4

How many irreversible reactions are there in the energy investment phase of glycolysis?

Back 4

2

Front 5

How many moles of ATP per mole of glucose are used in the energy investment phase of glycolysis?

Back 5

2

Front 6

Where in the cell does glycolysis occur?

Back 6

In the cytosol.

Front 7

What is the balanced reaction for glycolysis?

Back 7

glucose + 2 NAD+ + 2ADP = 2 pyruvate + 2 NADH + 2ATP

Front 8

Which reactions in glycolysis consume ATP?

Back 8

Reactions 1 and 3

Front 9

Which reactions in glycolysis generate ATP via substrate level phosphorylation?

Back 9

Reactions 7 and 10

Front 10

Which are the energy capture steps in glycolysis?

Back 10

Reactions 6, 7 and 10

Front 11

Which reactions in glycolysis have a ∆G of approximately zero?

Back 11

Reactions 2, 4, 5, 6, 7, 8 and 9

Front 12

Which reactions in glycolysis have a large, negative ∆g?

Back 12

Reactions 1, 3 and 10.

Front 13

Which is the committing step in glycolysis?

Back 13

Reaction 3.

Front 14

What is the most potent activator of phosphofructokinase 1?

Back 14

Fructose-2,6-bisphosphate.

Front 15

Which reactions in glycolysis are coupled?

Back 15

Reactions 1 and 3.

Front 16

Which reactions in glycolysis are feedback inhibited?

Back 16

Reaction 3

Front 17

Which reaction in glycolysis is product inhibited?

Back 17

Reaction 1

Front 18

What are the suppressors of phosphofructokinase 1?

Back 18

ATP, NADH and Phosphoenolpyruvate

Front 19

What are the high energy intermediates of glycolysis?

Back 19

ATP, 1,3-bisphosphoglycerate and phosphoenolpyruvate.

Front 20

Which molecule activates pyruvate kinase?

Back 20

Fructose-1,6-bisphosphate.

Front 21

What molecule inhibits pyruvate kinase?

Back 21

ATP

Front 22

What is the gross ATP yield for the complete glycolysis of 1 mole of glucose?

Back 22

4 moles

Front 23

What is the net ATP yield for the complete glycolysis of 1 mole of glucose?

Back 23

2 moles

Front 24

Which enzyme catalyzes the reaction which links glycolysis to the Krebs cycle?

Back 24

The pyruvate dehydrogenase complex.

Front 25

What are the products of pyruvate dehydrogenation?

Back 25

Acetyl-CoA, NADH and CO2.

Front 26

Pyruvate moves from the cytosol to the inter-membrane space via a ______, and enters the matrix via ______.

Back 26

Porin, pyruvate translocase.

Front 27

Where is the pyruvate dehydrogenase complex located?

Back 27

In the matrix

Front 28

What is the role of the swinging arm in the pyruvate dehydrogenase complex?

Back 28

To transport the intermediates amongst the enzymes in the complex.

Front 29

What makes Acetyl-CoA a high-energy intermediate?

Back 29

The thioester bond.

Front 30

Can glycolysis take place under anaerobic conditions?

Back 30

Yes.

Front 31

What molecule links glycolysis with the Krebs cycle?

Back 31

Acetyl-CoA

Front 32

What are the important activators of the pyruvate dehydrogenase complex?

Back 32

NAD+ and Ca++

Front 33

What is the most important inhibitor of the pyruvate dehydrogenase complex?

Back 33

Acetyl-CoA

Front 34

What is pyruvate converted to in the absense of oxygen?

Back 34

Lactate

Front 35

What is pyruvate converted to in the presence of oxygen?

Back 35

Acetyl-CoA

Front 36

In which cellular compartment does the Krebs cycle occur?

Back 36

The matrix

Front 37

Which are the energy capture steps in the Krebs cycle (counting pyruvate decarboxylation as Reaction 1)?

Back 37

Reactions 1, 4, 5, 6, 7 and 9.

Front 38

How many moles of CO2 result from the complete oxidation of 1 mole of pyruvate?

Back 38

3

Front 39

Which are the irreversible reactions in the Krebs cycle (counting pyruvate decarboxylation as Reaction 1)?

Back 39

Reactions 1, 3 and 4.

Front 40

Which reactions in the Krebs cycle produce CO2 (counting pyruvate decarboxylation as Reaction 1)?

Back 40

Reactions 1, 4 and 5

Front 41

Which reactions in the Krebs cycle produce nucleoside triphosphates (counting pyruvate decarboxylation as Reaction 1)?

Back 41

Reaction 6

Front 42

Which reactions in the Krebs cycle produce NADH (counting pyruvate decarboxylation as Reaction 1)?

Back 42

Reactions 1, 4, 5 and 9

Front 43

Which reactions in the Krebs cycle produce FADH2 (counting pyruvate decarboxylation as Reaction 1)?

Back 43

Reaction 7

Front 44

Which reactions in the Krebs cycle produce electron carriers (counting pyruvate decarboxylation as Reaction 1)?

Back 44

Reactions 1, 4, 5, 7 and 9

Front 45

Which reactions in the Krebs cycle are regulated (counting pyruvate decarboxylation as Reaction 1)?

Back 45

Reactions 1, 4, 5 and 9.

Front 46

What is the most important regulator of the Krebs cycle?

Back 46

The local NAD+:NADH ratio.

Front 47

Which enzyme in the Krebs cycle is an integral protein?

Back 47

Succinate dehydrogenase.

Front 48

Which molecules act as repressors of alpha-ketoglutarate dehydrogenase?

Back 48

ATP and NADH

Front 49

Which enzymes in the Krebs cycle are activated by Ca++?

Back 49

The pyruvate dehydrogenase complex and alpha-ketoglutarate dehydrogenase.

Front 50

Which molecules activate isocitrate dehydrogenase?

Back 50

ADP, AMP and NAD+