Exam (elaborations) BIOLOGY 206

OpenStax Microbiology Test Bank
Chapter 9: Microbial Growth

Chapter 9: Microbial Growth

* = Correct answer

Multiple Choice

1. Bacteria most commonly reproduce using which of the following methods?
A. binary fission*
B. budding
C. meiosis
D. mitosis

Difficulty: Easy
ASM Standard: N/A

2. Which structure separates new daughter cells in binary fission?
A. the crescent
B. the division septum*
C. the FtsZ
D. the spindle apparatus

Difficulty: Easy
ASM Standard: N/A

3. Which of the following is another term for generation time?
A. doubling time*
B. growth rate
C. mitotic index
D. replication index

Difficulty: Easy
ASM Standard: N/A

4. Which of the following best describes culture density?
A. another term for a batch culture
B. the number of cells per unit volume*
C. the reproducible pattern of growth
D. the total number of cells

Difficulty: Easy
ASM Standard: 36

5. Which of the following is the correct order of phases of growth in the growth curve of a
batch culture?
A. death/decline phase  lag phase  log phase  stationary phase
B. lag phase  log phase  stationary phase  death/decline phase *

Page 1 of 18

,OpenStax Microbiology Test Bank
Chapter 9: Microbial Growth

C. log phase  lag phase  stationary phase  death/decline phase
D. stationary phase  log phase  lag phase  death/decline phase

Difficulty: Easy
ASM Standard: 36

6. Which of the following is not a common way bacteria divide?
A. binary fission
B. budding
C. fragmentation
D. sporulation*

Difficulty: Moderate
ASM Standard: N/A

7. Which of the following is the term for free-living bacteria?
A. biofilms
B. pathogenic
C. planktonic*
D. sessile

Difficulty: Easy
ASM Standard: 21

8. Which of the following is not a reactive oxygen species?
A. atmospheric oxygen*
B. peroxides
C. singlet oxygen
D. superoxide

Difficulty: Easy
ASM Standard: 14

9. Which of the following best describes FtsZ?
A. a cytoskeletal protein in eukaryotic cells
B. the protein that assembles the Z ring, which forms a divisome before division by binary
fission*
C. the protein that forms within the central structure of the new cell wall and septum that
separates the daughter cells during binary fission
D. the protein that gives structure to spirochetes, contributing to their unusual shape and
motility

Difficulty: Moderate
ASM Standard: N/A

10. Which microbial pathogen has an unusually long doubling time?

Page 2 of 18

, OpenStax Microbiology Test Bank
Chapter 9: Microbial Growth

A. Bacillus subtilis
B. Escherichia coli
C. Mycobacterium leprae*
D. Salmonella typhimurium

Difficulty: Moderate
ASM Standard: N/A

11. The initial cells added to a batch culture are called which of the following?
A. the batch
B. the culture
C. the inoculum*
D. the lagging cells

Difficulty: Moderate
ASM Standard: 36

12. Which best describes bacterial growth during the log phase of the growth curve?
A. exponential*
B. linear
C. S-shaped
D. stationary

Difficulty: Moderate
ASM Standard: N/A

13. Which best defines the term “persisters?”
A. cells that form endospores rapidly when environmental conditions become unfavorable,
allowing them to survive in a dormant state without causing disease symptoms
B. cells that persist in the log phase for much longer than other cells
C. cells that rapidly colonize new environments by releasing virulence factors and moving
through tissues, allowing them to contribute to severe systemic infections.
D. cells with relatively slow metabolic rates that survive longer than others during the death
phase and that can cause chronic infections*

Difficulty: Moderate
ASM Standard: 14, 23

14. Which type of system is used to maintain bacteria in a relatively constant environment,
allowing them to stay in the log phase of growth?
A. bacteriostat
B. chemostat*
C. maintenance state
D. stable state

Difficulty: Moderate

Page 3 of 18