Question 1

Figure 6.1
  
-In Figure 6.1, which line best depicts a facultative anaerobe in the absence of O2?

Accepted Answer

A)  a 
B)  b 
C)  c 
A)  a 
B)  b 
C)  c

Question 2

Most fungi grow best at pH

Accepted Answer

A)  1. 
B)  5. 
C)  7. 
D)  9. 
E)  14. 
A)  1. 
B)  5. 
C)  7. 
D)  9. 
E)  14.

Question 3

Which of the following is an advantage of the standard plate count?

Accepted Answer

A)  provides immediate results 
B)  determines the number of viable cells 
C)  can be used to count heat- sensitive bacteria 
D)  can be performed on very dilute samples, such as lake water 
E)  can readily count cells that form aggregates 
A)  provides immediate results 
B)  determines the number of viable cells 
C)  can be used to count heat- sensitive bacteria 
D)  can be performed on very dilute samples, such as lake water 
E)  can readily count cells that form aggregates

Question 4

Which enzyme catalyzes the reaction: O2- + O2- + 2H+ -H2O2 + O2?

Accepted Answer

A)  oxidase 
B)  peroxidase 
C)  superoxide dismutase 
D)  catalase 
A)  oxidase 
B)  peroxidase 
C)  superoxide dismutase 
D)  catalase

Question 5

Which of the following elements is NOT correctly matched with its cellular function?

Accepted Answer

A)  phosphorus - incorporated into nucleic acids 
B)  magnesium and potassium - required as cofactors for enzymes 
C)  nitrogen - needed for amino acid synthesis 
D)  sulfur - used for synthesis of thiamin and biotin 
E)  None of the answers is correct; all of the elements are correctly matched. 
A)  phosphorus - incorporated into nucleic acids 
B)  magnesium and potassium - required as cofactors for enzymes 
C)  nitrogen - needed for amino acid synthesis 
D)  sulfur - used for synthesis of thiamin and biotin 
E)  None of the answers is correct; all of the elements are correctly matched.

Question 6

Agar is used as a solidifying agent in microbiological media since few bacteria can degrade it.

Accepted Answer

A) True 
 B)False

Question 7

Which enzyme catalyzes the reaction: 2H2O2 -2H2O + O2?

Accepted Answer

A)  superoxide dismutase 
B)  catalase 
C)  oxidase 
D)  peroxidase 
A)  superoxide dismutase 
B)  catalase 
C)  oxidase 
D)  peroxidase

Question 8

Pure cultures can easily be obtained on streak plates, even if the desired bacteria are present in very low concentrations.

Accepted Answer

A) True 
 B)False

Question 9

Which of the following pairs is mismatched?

Accepted Answer

A)  mesophile - growth at 25°C 
B)  thermophile - growth at 37°C 
C)  psychrophile - growth at 15°C 
D)  hyperthermophiles - growth at 85°C 
E)  psychrotroph - growth at 0°C 
A)  mesophile - growth at 25°C 
B)  thermophile - growth at 37°C 
C)  psychrophile - growth at 15°C 
D)  hyperthermophiles - growth at 85°C 
E)  psychrotroph - growth at 0°C

Question 10

If cells are grown in media containing amino acids labeled with radioactive nitrogen (15N), most of radioactivity will be found in the cells'

Accepted Answer

A)  DNA. 
B)  proteins. 
C)  phospholipids. 
D)  DNA and proteins. 
E)  DNA and phospholipids. 
A)  DNA. 
B)  proteins. 
C)  phospholipids. 
D)  DNA and proteins. 
E)  DNA and phospholipids.

Question 11

Figure 6.2
  
-Figure 6.2 shows a typical bacterial growth curve with the x- axis indicating the log of the number of bacteria and the y- axis indicating time in culture. In the figure, which section (or sections) shows a growth phase where the number of cells dying equals the number of cells dividing?

Accepted Answer

A)  a 
B)  b 
C)  c 
D)  d 
E)  a and c 
A)  a 
B)  b 
C)  c 
D)  d 
E)  a and c

Question 12

Figure 6.1
  
-In Figure 6.1, which line best depicts a psychrotroph incubated at 0°C?

Accepted Answer

A)  a 
B)  b 
C)  c 
A)  a 
B)  b 
C)  c

Question 13

Which of the following is NOT a direct method to measure microbial growth?

Accepted Answer

A)  metabolic activity 
B)  filtration 
C)  standard plate count 
D)  most probable number (MPN) 
E)  direct microscopic count 
A)  metabolic activity 
B)  filtration 
C)  standard plate count 
D)  most probable number (MPN) 
E)  direct microscopic count

Question 14

Table 6.1
Three different culture media are shown below. $\begin{array} { l l l } 
\text { Medium A } & \text { Medium B } & \text { Medium } \mathrm { C } \
\mathrm { Na } _ { 2 } \mathrm { HPO } _ { 4 } & \text { Tide detergent } & \text { Glucose } \
\mathrm { KH } _ { 2 } \mathrm { PO } _ { 4 } & \mathrm { Na } _ { 2 } \mathrm { HPO } _ { 4 } & \text { Peptone } \
\mathrm { MgSO } _ { 4 } & \mathrm { KH } _ { 2 } \mathrm { PO } _ { 4 } & \left( \mathrm { NH } _ { 4 } \right) _ { 2 } \mathrm { SO } _ { 4 } \
\mathrm { CaCl } _ { 2 } & \mathrm { MgSO } _ { 4 } & \mathrm { KH } _ { 2 } \mathrm { PO } _ { 2 } \
\mathrm { NaHCO } _ { 3 } & \left( \mathrm { NH } _ { 4 } \right) _ { 2 } \mathrm { SO } _ { 4 } & \mathrm { Na } _ { 2 } \mathrm { HPO } _ { 4 }
\end{array}$
-In Table, 6.1, in which medium (or media) would an autotroph grow?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  A and B 
E)  A and C 
A)  A 
B)  B 
C)  C 
D)  A and B 
E)  A and C

Question 15

Table 6.2
The following data show growth of two bacteria on different media.
 $$\begin{array}{l}
\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\quad\text { Amount of Growth }\
\begin{array} { | l | c | c | } 
 \hline & \text { Staphylococcus avoeus } & \text { Streptococcus pyogenes } \
\hline \text { Nutrient agar } & + + & + + \
\hline \text { Nutrient agar + 7.5\% NaCl } & + & - \
\hline
\end{array}
\end{array}$$
-The data in Table 6.2 indicate that S. aureus is a(n)

Accepted Answer

A)  facultative halophile. 
B)  aerobe. 
C)  facultative anaerobe. 
D)  halophile. 
E)  mesophile. 
A)  facultative halophile. 
B)  aerobe. 
C)  facultative anaerobe. 
D)  halophile. 
E)  mesophile.

Question 16

Figure 6.3
  
-In Figure 6.3, which tube shows the expected growth pattern for a microaerophile?

Accepted Answer

A)  a 
B)  b 
C)  c 
D)  d 
E)  e 
A)  a 
B)  b 
C)  c 
D)  d 
E)  e

Question 17

A culture medium consisting of agar, peptone, and beef heart is a

Accepted Answer

A)  chemically defined medium. 
B)  reducing medium. 
C)  selective medium. 
D)  complex medium. 
E)  differential medium. 
A)  chemically defined medium. 
B)  reducing medium. 
C)  selective medium. 
D)  complex medium. 
E)  differential medium.

Question 18

Which group of microorganisms is most likely to spoil a freshwater trout preserved with salt?

Accepted Answer

A)  facultative halophiles 
B)  anaerobes 
C)  hyperthermophiles 
D)  psychrophiles 
E)  thermophiles 
A)  facultative halophiles 
B)  anaerobes 
C)  hyperthermophiles 
D)  psychrophiles 
E)  thermophiles

Question 19

An experiment began with 4 cells and ended with 128 cells. How many generations did the cells go through?

Accepted Answer

A)  64 
B)  32 
C)  6 
D)  5 
E)  4 
A)  64 
B)  32 
C)  6 
D)  5 
E)  4

Question 20

Most pathogenic bacteria are thermophiles.

Accepted Answer

A) True 
 B)False

Exam 6: Microbial Growth

Figure 6.1 -In Figure 6.1, which line best depicts a facultative anaerobe in the absence of O2?

Most fungi grow best at pH

Which of the following is an advantage of the standard plate count?

Which enzyme catalyzes the reaction: O2- + O2- + 2H+ -H2O2 + O2?

Which of the following elements is NOT correctly matched with its cellular function?

Agar is used as a solidifying agent in microbiological media since few bacteria can degrade it.

Which enzyme catalyzes the reaction: 2H2O2 -2H2O + O2?

Pure cultures can easily be obtained on streak plates, even if the desired bacteria are present in very low concentrations.

Which of the following pairs is mismatched?

If cells are grown in media containing amino acids labeled with radioactive nitrogen (15N), most of radioactivity will be found in the cells'

Figure 6.1 -In Figure 6.1, which line best depicts a psychrotroph incubated at 0°C?

Which of the following is NOT a direct method to measure microbial growth?

Table 6.1 Three different culture media are shown below. Medium A Medium B Medium Tide detergent Glucose Peptone -In Table, 6.1, in which medium (or media) would an autotroph grow?

Table 6.2 The following data show growth of two bacteria on different media. Amount of Growth Staphylococcus avoeus Streptococcus pyogenes Nutrient agar ++ ++ Nutrient agar + 7.5\% NaCl + - -The data in Table 6.2 indicate that S. aureus is a(n)

Figure 6.3 -In Figure 6.3, which tube shows the expected growth pattern for a microaerophile?

A culture medium consisting of agar, peptone, and beef heart is a

Which group of microorganisms is most likely to spoil a freshwater trout preserved with salt?

An experiment began with 4 cells and ended with 128 cells. How many generations did the cells go through?

Most pathogenic bacteria are thermophiles.

The Microbial World and You

Chemical Principles

Observing Microorganisms Through a Microscope

Functional Anatomy of Prokaryotic and Eukaryotic Cells

Microbial Metabolism

The Control of Microbial Growth

Microbial Genetics

Biotechnology and Recombinant Dna

Classification of Microorganisms

The Prokaryotes: Domains Bacteria and Archaea

The Eukaryotes: Fungi, Algae, Protozoa, and Helminths

Viruses, Viroids, and Prions

Principles of Disease and Epidemiology

Microbial Mechanisms of Pathogenicity

Innate Immunity: Nonspecific Defenses of the Host

Adaptive Immunity: Specific Defenses of the Host

Practical Applications of Immunology

Disorders Associated With the Immune System

Antimicrobial Drugs

Microbial Diseases of the Skin and Eyes

Microbial Diseases of the Nervous System

Microbial Diseases of the Cardiovascular and Lymphatic Systems

Microbial Diseases of the Respiratory System

Microbial Diseases of the Digestive System

Microbial Diseases of the Urinary and Reproductive Systems

Environmental Microbiology

Applied and Industrial Microbiology

Filters

Figure 6.1 -In Figure 6.1, which line best depicts a facultative anaerobe in the absence of O₂?

Which enzyme catalyzes the reaction: O₂- + O₂- + 2H⁺-H₂O₂+ O₂?

Which enzyme catalyzes the reaction: 2H₂O2 -2H₂O + O₂?

If cells are grown in media containing amino acids labeled with radioactive nitrogen (¹⁵N), most of radioactivity will be found in the cells'