Metabolism II

Question 1

What are the regulators in Glycogen synthesis?

Answer 1

(+) Glucose, insulin; (-) epinephrine, glucagon (p.97)

Question 2

What are the regulators in Glycogenolysis?

Answer 2

(+) AMP, epinephrine, glucagon; (-) ATP, insulin (p.97)

Question 3

What are the regulators in the HMP shunt?

Answer 3

(+) NADP+; (-) NADPH (p.97)

Question 4

What are the regulators in de novo purine synthesis?

Answer 4

(-) AMP, IMP, GMP (p.97)

Question 5

What are the regulators in the Urea cycle?

Answer 5

(+) N-acetylglutamate (p.97)

Question 6

What are the regulators in Fatty Acid Synthesis?

Answer 6

(+) Insulin, citrate; (-) glucagon, palmitoyl-CoA (p.97)

Question 7

What are the regulators in Fatty Acid oxidation?

Answer 7

(-) Malonyl-CoA (p.97)

Question 8

What are the regulators in Cholesterol synthesis?

Answer 8

(+) insulin, thyroxine; (-) glucagon, cholesterol (p.97)

Question 9

How many ATP are produced by aerobic metabolism of glucose?

Answer 9

32 via the malate-aspartate shuttle in the heart and liver; 30 via the glycerol-3-phosphate shuttle in muscle (p.99)

Question 10

How many ATP are produced by anaerobic metabolism of glucose?

Answer 10

2 ATP per glucose molecule (p.99)

Question 11

What important substrate is carried by ATP?

Answer 11

Phosphoryl groups (p.99)

Question 12

What important substrate is carried by NADH, NADPH, FADH2?

Answer 12

Electrons (p.99)

Question 13

What important substrate is carried by Coenzyme A, lipoamide?

Answer 13

Acyl groups (p.99)

Question 14

What important substrate is carried by Biotin?

Answer 14

CO2 (p.99)

Question 15

What important substrate is carried by Tetrahydrofolates?

Answer 15

1-carbon units (p.99)

Question 16

What important substrate is carried by SAM?

Answer 16

CH3 groups (p.99)

Question 17

What important substrate is carried by TPP?

Answer 17

Aldehydes (p.99)

Question 18

What vitamin is NAD+ derived from?

Answer 18

Vitamin B3 (p.99)

Question 19

What vitamin is FAD+ derived from?

Answer 19

Vitamin B2 (p.99)

Question 20

What processes most commonly use NAD+?

Answer 20

Catabolic processes to carry reducing equivalents away as NADH (p.99)

Question 21

What processes most commonly use NADPH?

Answer 21

Anabolic processes (steroid and fatty acid synthesis) as a supply of reducing equivalents (p.99)

Question 22

Name for uses for NADPH.

Answer 22

Anabolic processes, respiratory burst, P-450, Glutathione reductase (p.99)

Question 23

What reaction is catalyzed by hexokinase/glucokinase?

Answer 23

Phosphorylation of glucose to yield Glucose-6-Phosphate in the first step of glycolysis and the first step of glycogen synthesis in the liver (p.99)

Question 24

Describe the kinetics of hexokinase.

Answer 24

Ubquitous; high affinity (low Km), low capacity (low Vmax); uninduced by insulin. Feedback inhibited by glucose-6-phosphate (p.99)

Question 25

Describe the kinetics of glucokinase.

Answer 25

Located in liver and beta cells of the pancreas. Low affinity (high Km), high capacity (high Vmax), induced by insulin (p.99)