Chapter 7 quiz

Which graph in Figure 7.2 best depicts the effect of placing the culture in an autoclave for 15 minutes at time x?

B

Table 7.3 The following data were obtained by incubating gram-positive bacteria in nutrient medium + disinfectant for 24 hours, then transferring one loopful to nutrient medium (subculturing). (+ = growth; - = no growth)

Doom

Which of the following is a limitation of the autoclave?

It cannot be used with heat-labile materials.

Table 7.1 A disk-diffusion test using Staphylococcus gave the following results: Disinfectant Zone of inhibition (mm) A 0 B 2.5 C 10 D 5

The answer cannot be determined based on the information provided.

Table 7.1 A disk-diffusion test using Staphylococcus gave the following results: Disinfectant Zone of inhibition (mm) A 0 B 2.5 C 10 D 5 In Table 7.1, which compound was the most effective against E. coli

The answer cannot be determined based on the information provided.

Which of the following best describes the pattern of microbial death?

The cells in a population die at a constant rate.

Which of the following pairs of terms is mismatched?

bacteriostatic - kills vegetative bacterial cells

Which of the following substances is used for surgical hand scrubs?

chlorhexidine

The most effective form of chlorine is which of the following?

hypochlorous acid

If you were preparing nutrient agar at home and did not have an autoclave, what could you use to sterilize the nutrient agar?

pressure cooker at 121°C for 15 minutes