Sterilization and Disinfection - Higher Difficulty Problems
Q. What is the primary advantage of using UV light for disinfection?
A.It is effective against all pathogens
B.It does not leave chemical residues
C.It is inexpensive
D.It penetrates surfaces effectively
Solution
The primary advantage of using UV light for disinfection is that it does not leave chemical residues, making it safe for use in sensitive environments.
Correct Answer: B — It does not leave chemical residues
Q. What is the primary disadvantage of using glutaraldehyde as a disinfectant?
A.It is ineffective against viruses
B.It requires long exposure times
C.It is corrosive to metals
D.It has a strong odor
Solution
The primary disadvantage of glutaraldehyde is its strong odor, which can be unpleasant and may pose health risks to users.
Correct Answer: D — It has a strong odor
Q. What is the primary mechanism of action for chlorine-based disinfectants?
A.Protein denaturation
B.Nucleic acid synthesis inhibition
C.Cell wall disruption
D.Enzyme inhibition
Solution
Chlorine-based disinfectants primarily act by denaturing proteins, which disrupts cellular functions.
Correct Answer: A — Protein denaturation
Q. What is the primary purpose of using a biological indicator in sterilization processes?
A.To measure the temperature of the sterilizer
B.To confirm the presence of pathogens
C.To verify the effectiveness of the sterilization process
D.To assess the chemical composition of the sterilant
Solution
The primary purpose of using a biological indicator is to verify the effectiveness of the sterilization process by demonstrating that spores have been killed.
Correct Answer: C — To verify the effectiveness of the sterilization process
Q. Which of the following disinfectants is effective against spores?
A.Alcohol
B.Chlorine
C.Hydrogen peroxide
D.Quaternary ammonium compounds
Solution
Hydrogen peroxide is effective against spores, especially at higher concentrations, making it a suitable disinfectant for various applications.
Correct Answer: C — Hydrogen peroxide
Q. Which of the following factors does NOT affect the efficacy of a disinfectant?
A.Concentration of the disinfectant
B.Presence of organic matter
C.Temperature
D.Color of the disinfectant
Solution
The color of the disinfectant does not affect its efficacy; however, concentration, organic matter, and temperature do.
Correct Answer: D — Color of the disinfectant
Q. Which of the following is a common indicator organism used to test the efficacy of sterilization?
A.Escherichia coli
B.Bacillus subtilis
C.Staphylococcus aureus
D.Pseudomonas aeruginosa
Solution
Bacillus subtilis spores are commonly used as biological indicators to test the efficacy of sterilization processes.
Correct Answer: B — Bacillus subtilis
Q. Which of the following is NOT a method of sterilization?
A.Filtration
B.Radiation
C.Boiling water
D.Autoclaving
Solution
Boiling water is not a reliable method of sterilization as it does not kill all spores and certain resistant pathogens.
Correct Answer: C — Boiling water
Q. Which of the following methods is most effective for sterilizing heat-sensitive instruments?
A.Autoclaving
B.Ethylene oxide gas
C.Dry heat sterilization
D.Chemical disinfection
Solution
Ethylene oxide gas is effective for sterilizing heat-sensitive instruments as it can penetrate materials without causing damage.
