Enzymes. Structure and general properties of enzymes

Choose the one correct answer:

1. An enzymes:

A. are heat stable;

B. are simple proteins;

C. are not water- soluble;

D. is stabile to heating to strong acid;

E. are heat labile.

2. Which one of the following statements about the general characteristics of enzymes is incorrect?

A. almost all enzymes are proteins;

B. they contain 16% weight as nitrogen;

C. they are water- soluble;

D. they can be precipitate by protein precipitating reagents;

E. is stabile to heating to strong acid.

3. What is the substrate?

A. a simple or conjugated proteins;

B. the substance upon which an enzyme acts;

C. the protein component of holo enzyme;

D. the non-protein component of holo enzymes;

E. an inorganic component of holo enzymes.

4. What is the cofactor?

A. a simple or conjugated proteins;

B. the substance upon which an enzyme acts;

C. the protein component of holo enzyme;

D. the non-protein component of holo enzymes;

E. an inorganic component of holo enzymes.

5. What is the Apo Enzyme?

A. a simple or conjugated proteins;

B. the substance upon which an enzyme acts;

C. the protein component of holo enzyme;

D. the non-protein component of holo enzymes;

E. an inorganic component of holo enzymes

6. What are the zymogens?

A. a simple or conjugated proteins;

B. inactive forms of enzyme;

C. the enzymes having similar catalytic activity, act on the same substrate and produces the same product but originated at different site and exhibiting different physical and chemical characteristics such as electrophoretic mobilities, amino acid composition and immunological behavior;

D. the non-protein component of holo enzymes;

E. an inorganic component of holo enzymes

7. What are the Isozymes?

A. a simple or conjugated proteins;

B. inactive forms of enzyme;

C. the enzymes having similar catalytic activity, act on the same substrate and produces the same product but originated at different site and exhibiting different physical and chemical characteristics such as electrophoretic mobilities, amino acid composition and immunological behavior;

D. the non-protein component of holo enzymes;

E. an inorganic component of holo enzymes

8. Which one of the following statements about holo enzymes is correct?

A. all holo enzymes are simple proteins;

B. holo enzymes are made up from protein groups and non-protein component;

C. holo enzymes are inactive forms of enzymes;

D. holo enzymes have not active Centre;

E. holo enzymes are simple or conjugate proteins.

9. What types of LDG do you know?

A.HHHH

B. HHHB

C. HHBB

D. HBBB

E. BBBB

10. What classes of enzymes do you know?

A. simple proteins, conjugated proteins;

B. zymogenes and isozymes;

C. holoenzymes, simple proteins;

D. Oxidoreductases, transferases, hydrolases, lyases, isomerases, ligases, isozymes;

E. Oxidoreductases, transferases, hydrolases, lyases, isomerases, ligases.