Enzymes: structure and properties

Lesson 4

Enzymes: structure and properties

Variant 3

1. The role of allosteric site is:

E. interaction with substrate molecules;

F. assembling on the membrane surface;

G. participation in enzymatic reaction;

H. interaction with activators and inhibitors.

2. What is the function of the hydrolases?

A. To catalyze racemization of optical or geometric isomers.

B. To catalyze cleavage of bonds by addition of water.

C. To catalyze transfer of C, N or P-containing groups.

D. To catalyze cleavage of C-C, C-S and certain C-N bonds.

3. At extreme pH or temperature enzymes:

A. have a high activity;

B. catalyze a direct and a reverse reaction;

C. are denatured;

D. speed up chemical reaction.

4. Enzymes are catalysts of protein's nature. They are:

A. highly specific in nature;

B. temperature liable;

C. active in pH optimum;

D. all of the above.

5. All of the following statements about enzymes are true EXCEPT:

A. enzymes catalyze only direct reaction;

B. enzymes speed up chemical reaction;

C. enzymes are not used in chemical reaction;

D. enzymes catalyze a direct and a reverse reaction.