16. When substrate [S] = K_M (Michaelis-Menten constant), the velocity of an enzyme-catalyzed reaction is about

A. 0.1 * V_max
B. 0.2 * V_max
C. 0.5 * V_max
D. 0.9 * V_max

17. A classical noncompetitive inhibitor has

A. no effect on substrate binding
B. no effect on substrate binding and vice versa
C. significant effect on substrate binding
D. significant effect on substrate binding and vice versa

18. The active site of an enzyme differs from an antibody-antigen binding site in that the enzyme active site

A. contains modified amino acids
B. catalyzes a chemical reaction
C. is complementary to a specific ligand
D. contains amino acids without side chains

19. Enzymes are basically

A. proteins
B. vitamins
C. fat
D. carbohydrates

20. Which of the following refers to pseudo steady-state?

A. d(C_E)/dt = 0
B. d(C_p)/dt = 0
C. d(C_ES)/dt = 0
D. d(C_s)/dt = d(C_ES)/dt