chap 7 eoc multiple choice

What bacteria have porins, are resistant to bisphenols,

and survive and may grow in quats?

Escherichia coli or Pseudomonads

Which of the following does not kill endospores?

a. autoclaving

b. incineration

c. hot-air sterilization

d. pasteurization

e. All of the above kill

endospores

pasteurization

3. Which of these disinfectants does not act by disrupting the plasma

membrane?

a. phenolics

b. phenol

c. quats

d. halogens

e. biguanides

halogens

4. Which of the following cannot be used to sterilize a heat-labile

solution stored in a plastic container?

a. gamma radiation

b. ethylene oxide

c. supercritical fluids

d. autoclaving

e. short-wavelength radiation

autoclaving

5. Which of the following is used to control microbial growth in foods?

a. organic acids

b. alcohols

c. aldehydes

d. heavy metals

e. all of the above

organic acids

Which of the following is not a characteristic of quaternary

ammonium compounds?

a. bactericidal against gram-positive bacteria

b. sporicidal

c. amebicidal

d. fungicidal

e. kills enveloped viruses

sporicidal

8. Which of the following is most likely to be bactericidal?

a. membrane filtration

b. ionizing radiation

c. lyophilization (freeze-drying)

d. deep-freezing

e. all of the above

ionizing radiation

9. You and your classmates are trying to determine how a disinfectant

might kill cells. You observe that when you spill the disinfectant

in a tube of reduced litmus milk, the litmus turns blue again. You

suggest to your classmates that

a. the disinfectant might inhibit cell wall synthesis.

b. the disinfectant might oxidize molecules.

c. the disinfectant might inhibit protein synthesis.

d. the disinfectant might denature proteins.

e. the disinfectant might damage DNA.

the disinfectant might oxidize molecules.

Use the following information to answer questions 6 and 7. The data were obtained from a use-dilution test comparing four disinfectants against Salmonella Choleraesuis. G N = = growth, G no growth

6. Which disinfectant is the most effective?

Disinfectant A

11. Which disinfectant(s) is (are) bactericidal?

a. A, B, C, and D

b. A, C, and D

c. A only

d. B only

e. none of the above

A,C and D

Which of the following is most effective for sterilizing mattresses

and plastic Petri dishes?

a. chlorine

b. ethylene oxide

c. glutaraldehyde

d. autoclaving

e. nonionizing radiation

ethylene oxide