CA cycle

Question 1

What is the first reaction of CA cycle?

Answer 1

Acetyl Coa + oxaloacetate into citrate by citrate synthase

Question 2

What is the second reaction of CA cycle?

Answer 2

Citrate into isocitrate by aconitase

Question 3

What is the third reaction of the CA cycle?

Answer 3

Isocitrate into alpha-ketogluterate by isocitrate dehydrogenase using NAD

Question 4

What are the other products of the third reaction of the CA cycle?

Answer 4

NADH + H
CO2

Question 5

What is the fourth reaction of the CA cycle?

Answer 5

Alpha-ketogluterate to Succinyl CoA using alpha-ketogluterate dehydrogenase using CoASH and NAD

Question 6

What are the other products of the fourth reaction of the CA cycle?

Answer 6

NADH + H
CO2

Question 7

What are the coenzymes of alpha-ketogluterate dehydrogenase?

Answer 7

TPP
Lipoamide
CoA

Question 8

What is the fifth reaction of the CA cycle?

Answer 8

Succinyl CoA into Succinate by succinyl CoA synthetase using GDP and Pi

Question 9

What are the other products of fifth reaction of the CA cycle?

Answer 9

CoASH
GTP

Question 10

What is the sixth reaction of the CA cycle?

Answer 10

Succinate to fumarate by succinate dehydrogenase using FAD

Question 11

What is the other product of the sixth reaction of CA cycle?

Answer 11

FADH2

Question 12

What is the seventh reaction of the CA cycle?

Answer 12

Fumarate to Malate using fumarase

Question 13

What is the eighth and final reaction of the CA cycle?

Answer 13

Malate into oxaloacetate by malate dehydrogenase using NAD

Question 14

What is the other product of the final step of the CA cycle?

Answer 14

NADH + H

Question 15

What inhibits aconitase?

Answer 15

Fluorocitrate

Question 16

How is fluorocitrate formed?

Answer 16

Fluoracetate (poison) condenses with oxaloacetate

Question 17

What poison inhibits alpha-ketoglutarate dehydrogenase?

Answer 17

Arsenite

Question 18

What enzyme of the CA cycle is bound to the IMM?

Answer 18

Succinate dehydrogenase

Question 19

What are the typical regulatory enzymes of the CA cycle?

Answer 19

Citrate synthase
Isocitrate dehydrogenase
Alpha-ketoglutarate dehydrogenase

Question 20

What allosterically inhibits citrate synthase?

Answer 20

ATP
Long chain fatty acyl CoA

Question 21

What allosterically stimulates isocitrate dehydrogenase?

Answer 21

ADP

Question 22

What allosterically inhibits isocitrate dehydrogenase?

Answer 22

NADH
ATP

Question 23

What inhibits alpha-ketoglutarate dehydrogenase?

Answer 23

Succinyl CoA
NADH
High energy charge (high level of ATP in cell)

Question 24

What inhibits succinyl dehydrogenase?

Answer 24

Oxaloacetate

Question 25

What does the availability of oxaloacetate depend on?

Answer 25

NADH/NAD ratio that affects malate dehydrogenase

Question 26

What enzymes are affected by arsenic poisoning?

Answer 26

PDH complex alpha-ketoglutarate dehydrogenase Alpha ketoacid dehydrogenase

Question 27

What part of the enzyme is affected by arsenic poisoning?

Answer 27

-SH group of lipoic acid

Question 28

How much NADH and FADH2 are produced by the CA cycle per glucose?

Answer 28

6 NADH 2 FADH

Question 29

How much energy is produced for each NADH that goes through ETC?

Answer 29

2.5 ATP

Question 30

How much energy is produced for each FADHs that goes through ETC?

Answer 30

1.5 ATP

Question 31

How much energy is produced by the CA cycle for each glucose?

Answer 31

20 ATP

Question 32

How much energy is produced for each glucose from glycolysis through TCA cycle?

Answer 32

32 ATP

Question 33

Other than energy production, why else is the CA cycle important?

Answer 33

Major pathway for gluconeogenesis, AA synthesis, and fatty acid synthesis

Question 34

What does amphibolic mean?

Answer 34

Functions as both oxidative/metabolic and synthetic/anabolic

Question 35

What are sources of acetyl CoA?

Answer 35

Palmitate Acetoacetate Pyruvate Ethanol

Question 36

What is the part of the CA cycle that is used in gluconeogenesis?

Answer 36

Oxaloacetate

Question 37

What is the part of the CA cycle used in fatty acid synthesis?

Answer 37

Acetyl CoA

Question 38

What is the vitamin found in FAD?

Answer 38

Riboflavin

Question 39

What is the vitamin found in NAD?

Answer 39

Niacin

Question 40

What is pantothenic acid a part of as a coenzyme?

Answer 40

Coenzyme A

Question 41

How is biotin used in the CA cycle?

Answer 41

CO2 fixation reaction for oxaloacetate concentration

Question 42

What is anaplerosis?

Answer 42

Replenishing CA cycle intermediates