Urgent Review - Exam 2

Question 1

Irreversible reaction of TCA cycle/pace setting enzyme

Answer 1

Citrate synthase

Question 2

Citrate synthase function

Answer 2

Oxaloacetate + acetyl to form citrate

Question 3

Citrate synthase activity is dependent on:

Answer 3

Oxaloacetate and acetyl CoA concentration

Question 4

Citrate synthase is inhibited by:

Answer 4

High level of citrate

Question 5

Isocitrate dehydrogenase is an enzyme of:

Answer 5

TCA cycle

Question 6

Isocitrate dehydrogenase stimulated by:

Answer 6

ADP

Question 7

Isocitrate dehydrogenase inhibited by:

Answer 7

NADH

Question 8

a-ketoglutarate dehydrogenase is inhibited by

Answer 8

Succinyl Coenzyme A (competes for CoA)

Question 9

If energy charge is high in TCA cycle:

Answer 9

oxaloacetate goes to glucose

Question 10

If energy charge is low in TCA cycle:

Answer 10

oxaloacetate replenishes the citric acid cycle

Question 11

NADH carries protons and electrons to

Answer 11

NADH-CoQ reductase (Complex 1)

Question 12

NAD+ is derived from

Answer 12

niacin B3

Question 13

NAD+ accepts

Answer 13

1 hydrogen and 2 electrons

Question 14

FAD+ is derived from

Answer 14

riboflavin B2

Question 15

FAD accepts

Answer 15

2 hydrogen ions and 2 electrons

Question 16

____ is an activated carrier of electrons for reductive biosynthesis

Answer 16

NADP+

Question 17

Coenzyme A vitamin precursor

Answer 17

Pantothenate B5

Question 18

Tetrahydrofolate vitamin precursor

Answer 18

Folate

Question 19

Reactive group of coenzyme A

Answer 19

Terminal sulfhydryl

Question 20

2 things that occur in liver mitochondria

Answer 20

Ketone body formation, urea cycle

Question 21

High ATP causes ____ to be allosterically inhibited and lowers affinity for fructose-6-p

Activated by AMP (low energy signal)

Answer 21

Phosphofructokinase

Question 22

Which steps in glycolysis make ATP

Answer 22

Phosphoglycerate kinase to form 3PG
Pyruvate kinase to form Pyruvate (last step)

Question 23

Which step in glycolysis uses ATP

Answer 23

Hexokinase to make G6P

Question 24

gluconeogenesis - conversion of pyruvate to PEP requires

Answer 24

Biotin

Question 25

Steps of pyruvate conversion into PEP

Answer 25

1. Pyruvate carboxylase converts pyruvate into Oxaloacetate 2. OAA converts to malate 3. malate leaves mitochondria into cytosol 4. malate converts into OAA 5. PEP carboxykinase turns OAA into PEP

Question 26

Regarding PFK2, insulin causes ____ to phosphorylate/dephosphorylate _____

Answer 26

Phosphoprotein phosphatase 1 (PP1); dephosphorylates PFK2 to activate the KINASE activity More F-2,6-BP More PFK1 activity More glycolysis

Question 27

Regarding PFK2, glucagon causes ____ to phosphorylate/dephosphorylate _____

Answer 27

cAMP dependent protein kinase A; phosphorylates to turn on PHOSPHATASE activity More F6P More gluconeogenesis Less glycolysis