26. Quinolones are

A. antimetabolites
B. penicillin derivatives
C. bacteriostatic
D. broad-spectrum

27. Which of the following is not a semi-synthetic chemotherapeutic agent?

A. Ampicillin
B. Carbenicillin
C. Penicillin
D. Sulfonamide

28. Which of the following tests is used to determine the minimal lethal concentration?

A. Broth dilution test
B. Agar dilution test
C. Dilution susceptibility tests
D. All of these

29. The mode of action of polymyxin is to

A. inhibit protein synthesis
B. inhibit DNA synthesis
C. injury to the plasma membrane
D. inhibit folic acid synthesis

30. Polyene antibiotics are

A. large ring structures
B. β-lactam – thiazolidine ring
C. small ring structures
D. any of these