Question 1

Which chemical agent is most effective at denaturing proteins and is commonly used in solutions like Betadine for skin antisepsis?

Accepted Answer

Halogens such as iodine

Question 2

A hospital uses ethylene oxide to sterilize surgical instruments. What is the primary mode of action for this gaseous sterilant?

Accepted Answer

Alkylates nucleic acids

Question 3

Which antimicrobial drug is most appropriate for treating tuberculosis and acts as a cell wall inhibitor?

Accepted Answer

Isoniazid

Question 4

A patient allergic to penicillin is prescribed cephalexin. What is the shared mode of action between these two drugs?

Accepted Answer

Inhibition of cell wall synthesis

Question 5

Which chemical agent is used in triple antibiotic ointment and acts by inhibiting protein synthesis at the 30S ribosomal subunit?

Accepted Answer

Neomycin

Question 6

A microbiologist is testing the effectiveness of 70% isopropanol as a disinfectant. Which of the following best describes its mode of action?

Accepted Answer

Denatures proteins and dissolves cell membranes

Question 7

Which antimicrobial drug inhibits RNA polymerase and is used to treat tuberculosis?

Accepted Answer

Rifampin

Question 8

A patient is prescribed ciprofloxacin for a urinary tract infection. What is the primary mode of action of this drug?

Accepted Answer

Inhibits DNA synthesis

Question 9

Which chemical agent is most likely to be used for mechanical removal of microbes due to its bubbling action?

Accepted Answer

Hydrogen peroxide

Question 10

A patient with a MRSA infection is prescribed Synercid. What is the mode of action of this drug?

Accepted Answer

Inhibits protein synthesis at the 50S ribosomal subunit

Question 11

Which chemical agent is most effective against bacterial spores and is used for sterilizing heat-sensitive medical equipment?

Accepted Answer

Ethylene oxide

Question 12

A patient is prescribed sulfanilamide for a bacterial infection. What is the primary mode of action of sulfa drugs?

Accepted Answer

Inhibits folic acid synthesis (metabolism)

Question 13

Which chemical agent is commonly used in mouthwashes and acts by disrupting cell membranes and protein function?

Accepted Answer

Phenols such as hexachlorophene

Question 14

A patient is prescribed erythromycin for a respiratory infection. What is the mode of action of macrolides?

Accepted Answer

Inhibits protein synthesis at the 50S ribosomal subunit

Question 15

Which chemical agent is used as a topical antiseptic and acts primarily by denaturing proteins?

Accepted Answer

Iodine

Question 16

A patient is prescribed tetracycline for acne. What is the mode of action of tetracyclines?

Accepted Answer

Inhibits protein synthesis at the 30S ribosomal subunit

Question 17

Which chemical agent is used in wound care and acts by denaturing proteins, but can also be toxic to human tissues?

Accepted Answer

Heavy metals such as silver nitrate

Question 18

A patient is prescribed vancomycin for a resistant bacterial infection. What is the primary mode of action of vancomycin?

Accepted Answer

Inhibits cell wall synthesis

Question 19

Which chemical agent is most effective as a degerming agent before injections, and why is 70% alcohol preferred over 100% alcohol?

Accepted Answer

70% alcohol is preferred because it denatures proteins more effectively due to the presence of water

Question 20

A patient is prescribed trimethoprim for a urinary tract infection. Which metabolic pathway is inhibited by this drug?

Accepted Answer

Folic acid synthesis

Chemical Agents of Control and Antimicrobial Treatments

Study Guide - Practice Questions