Cell Metabolism

Question 1

Where does the TCA cycle take place?

Answer 1

The mitochondrial matrix

Question 2

What is the most regulated step of Glycolysis?

Answer 2

Fructose 6-Phosphate –> Fructose 1,6-Bisphosphate

Question 3

What enzyme catalyzes the phosphorylation of Fructose 6-Phosphate to Fructose 1,6-Bisphosphate?

Answer 3

Phosphofructokinase-1

Question 4

What stimulates Phosphofructokinase-1 activity?

Answer 4

• AMP

- Fructose 2,6-bisphosphate

Question 5

What inhibits Phosphofructokinase-1 activity?

Answer 5

• ATP

- Citrate

Question 6

What enzyme catalyzes the conversion of 1,3-bisphosphoglycerate to 2,3-bisphosphoglycerate? Where is it located?

Answer 6

• Mutase

- Red Blood Cells

Question 7

What inhibits Hexokinase/Glucokinase activity?

Answer 7

Glucose 6-Phosphate

Question 8

What leads to Fructose 2,6-bisphosphate creation? Where does it occur?

Answer 8

A high insulin:glucagon ratio decreases levels of cAMP in liver cells. Decreased PKA activity leads to generation of fructose 2,6-bisphosphate

Question 9

What stimulates Pyruvate Kinase activity?

Answer 9

Fructose 1,6-Bisphosphate

Question 10

What does Pyruvate Kinase do?

Answer 10

Catalyzes the reaction Phosphoenolpyruvate + ADP –> Pyruvate + ATP

Question 11

What is the purpose of anaerobic Glycolysis?

Answer 11

Regeneration of NAD+ for use in Glycolysis

Question 12

What does Lactate Dehydrogenase do?

Answer 12

Catalyzes the creation of Lactate from Pyruvate

Question 13

What is the Cori Cycle?

Answer 13

A cycle that takes Lactate from the muscles produced by anaerobic glycolysis, to the liver to be converted back to glucose to return to the muscles.

Question 14

What enzyme converts Pyruvate to Acetyl CoA?

Answer 14

Pyruvate Dehydrogenase (PDH)

Question 15

What inhibits PDH?

Answer 15

• Acetyl CoA

- NADH

Question 16

What disease results form Vitamin B1/TPP deficiency?

Answer 16

Beriberi

Question 17

What are the symptoms of Beriberi?

Answer 17

• GI Sx’s

- Neurological findings

Question 18

What is vitamin b2?

Answer 18

Riboflavin

FAD/FADH2

Question 19

What are the symptoms of Vitamin B2/Riboflavin deficiency?

Answer 19

• Fissures in mouth
• Inflammation of tongue
• Skin disease
• Severe irritation of the eyes

Question 20

What disease results from Vitamin B3/Niacin deficiency?

Answer 20

Pellegra

Question 21

What are the Sx’s of Pellegra?

Answer 21

• Skin Disease
• Diarrhea
• dementia
• Death

Question 22

What are the inhibitors of the TCA cycle?

Answer 22

• ATP
• Acetyl CoA
• NADH
• Citrate
• Malonyl-CoA

Question 23

What are the activators of the TCA cycle?

Answer 23

• AMP
• ADP
• NAD
• Ca2+
• cAMP
• CoASH

Question 24

What are the Structures of the electron transport chain in order of electron flow?

Answer 24

• NADH Dehydrogenase -or- Succinate Dehydrogenase
• Ubiquinone/Coenzyme Q
• Cytochrome b-c1 complex
• Cytrochrome C
• Cytochrome Oxidase
• O2

Question 25

What does NADH dehydrogenase use to transfer electrons?

Answer 25

iron-sulfer clusters

Question 26

How many electrons can coenzyme Q carry?

Answer 26

2

Question 27

How many electrons does cytochrome C carry?

Answer 27

1

Question 28

How many electrons enter cytochrome c oxidase at one time?

Answer 28

4

Question 29

How many protons must flow through ATPase to generate 1 ATP?

Answer 29

3

Question 30

What are 2 NADH dehydrogenase inhibitors?

Answer 30

• Amytal

- Rotenone

Question 31

What is a cytochrome b-c1 complex inhibitor?

Answer 31

Antimycin A

Question 32

What are 3 Cytochrome C oxidase inhibitors?

Answer 32

• CN
• CO
• Azide

Question 33

What is an ATPase inhibitor?

Answer 33

-oligomycin

Question 34

What are two ATP/ADP exchange inhibitors?

Answer 34

• Atractyloside

- Bongkrektate

Question 35

What are two uncouplers of respiration? What do they do?

Answer 35

-FCCP and NDP

They collapse the H+ Gradient