Biochemistry 2006
1. Which chemical bonds can be found in Glycogen?
a. a 1-4 Glycosid bonds
b. b 1-6 Glycosid bonds
c. Phosphate bonds
d. Peptide bonds
e. All of the above
2. What is Glycognin?
a. A protein that participates in the synthesis of Glycogen
b. A protein that is used as a primer in the synthesis of Glycogen
c. An enzyme that phosphorilates glycogen
d. A co-factor in glycogen degradation
3. Isoprin is an analog of Glutamin. Which of the following does it affect?
a. Purine synthesis
b. Utilization of Purines and Pyrimidines
c. Synthesis of Uric acid
d. Synthesis of Thymidine
e. a+c
f. a+b
4. What will you find if you measure the disappearance of Glucose and production of CO2 in a muscle cell culture in the absence of vitamin B12 ?
a. The disappearance of Glucose will increase and the CO2 level will decrease
b. The disappearance of Glucose will increase and the CO2 level will increase
c. The disappearance of Glucose will decrease and the CO2 level will decrease
d. The disappearance of Glucose will decrease and the CO2 level will increase
e. The disappearance of Glucose will not change and the CO2 level will increase
5. If you would mark the first carbon molecule of Glucose-6-phosphate, where will you find the marked carbon after the oxidation chain?
a. CO2 exhaled
b. C5 of Fructose
c. C1 of Fructose
6. Two enzymes have different Km, but have the same efficiency. .Km (I) = 10-9 ,
Km (II) = 10-3. How would you explain this ?
a. Kcat (II) = 106, Kcat(I) = 1
7. The levels of the enzyme Lactase can help diagnose:
a. Myocardial Infarction
b. Glycogen storage disease
c. A problem absorbing sugars in the GI tract
d. a+b
8. Which reaction is catalyzed by Enolase?
a. Lys. receives a proton
b. Lys. receives a Hydroxil
c. Glu. receives a proton
d. Glu. receives a Hydroxil
9. Mark the correct answer concerning enzymes?
a. An allosteric inhibitor connects to a site distant from the active site of the enzyme
b. A competitive inhibitor connects to a site distant from the active site of the enzyme
c. An enzyme does not change the equilibrium of the system
10. What is the electric change of the protein C-Glu-His-Lys-N in pH = 5.5 ?
a. +1
b. +2
c. 0
d. -1
11. A mutant enzyme catalyses the following reaction
Glyceraldehyde-3-phosphate --- > 3-phosphoglycerate. What are the consequences?
a. In anaerobic condition the existence of the bacteria will be compromised.
12. Which of the following compressions take place:
a. AcetylCoA + MalonylCoA
b. AcetylCoA + AcetylCoA
c. MalonylCoA +AcylCoA
d.
e. a+c
13. Mark the correct answer concerning b-sheets:
a. Side groups are 180° apart
b. The N terminal groups are on the same side.
Possible answers:
Question / Answer1 / a
2 / b
3 / a
4
5
6 / a
7 / c
8 / a
9 / b
10
11 / a
12
13 / a