Question 1

Which of the following best describes the process of binary fission in prokaryotes?

Accepted Answer

An asexual process where a single cell divides into two identical daughter cells.

Question 2

A hospital patient develops a persistent infection associated with a catheter. Which microbial growth phenomenon is most likely responsible for the persistence of this infection?

Accepted Answer

Biofilm formation

Question 3

A bacterium has a generation time of 30 minutes. If you start with 1 cell, how many cells will there be after 3 hours, assuming unlimited resources and no cell death? Use the formula $$N = N_0$ 	imes 2^n$$, where $$n is $$the number of generations.

Accepted Answer

$$N = 1 	imes 2^6$ = 64$$

Question 4

Which of the following environmental conditions would most likely inhibit the growth of a mesophile?

Accepted Answer

Incubation at 60°C

Question 5

Which adaptation allows acidophiles to survive in environments with pH \u003c 5?

Accepted Answer

They maintain a neutral cytoplasmic pH using proton pumps.

Question 6

A bacterium isolated from the Dead Sea is most likely a:

Accepted Answer

Halophile

Question 7

Which enzyme is responsible for converting superoxide ions to hydrogen peroxide in aerobic microbes?

Accepted Answer

Superoxide dismutase

Question 8

Which of the following best describes a facultative anaerobe?

Accepted Answer

Can grow with or without oxygen, switching between aerobic respiration and fermentation.

Question 9

Which of the following is a growth factor for a fastidious organism?

Accepted Answer

Amino acids

Question 10

Which type of media would you use to visually distinguish between bacteria that can ferment lactose and those that cannot?

Accepted Answer

Differential media

Question 11

A clinical sample is collected to test for an anaerobic pathogen. Which of the following is most important during sample collection?

Accepted Answer

Quickly seal the sample in specialized transport media to prevent oxygen exposure.

Question 12

Which of the following methods would be most appropriate for sterilizing a heat-sensitive solution in a plastic container?

Accepted Answer

Membrane filtration

Question 13

Which of the following statements about HEPA filters is correct?

Accepted Answer

They remove 99.97% of airborne substances with pores 0.3 μm or larger.

Question 14

Which of the following chemical agents is classified as a high-level germicide and can sterilize medical equipment?

Accepted Answer

Ethylene oxide

Question 15

Which physical control method is most effective for eliminating bacterial endospores from contaminated glassware?

Accepted Answer

Autoclaving at 121°C and 15 psi for 20 minutes

Question 16

A laboratory technician needs to count the number of viable bacteria in a water sample. Which method should they use?

Accepted Answer

Viable plate count with serial dilution

Question 17

Which of the following best describes the decimal reduction time ($$D$$ value) in microbial control?

Accepted Answer

The time in minutes it takes to kill 90% of a microbial population at a set temperature.

Question 18

Which of the following is NOT a method by which non-ionizing radiation controls microbial growth?

Accepted Answer

Generating reactive ions that damage nucleic acids

Question 19

Which of the following statements about prion control is correct?

Accepted Answer

Prions require a combination of chemical treatments and increased temperature and pressure for elimination.

Fundamentals of Microbial Growth: Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards