Question 1

Organisms that can survive inside or outside host cells are called ________ pathogens.

Accepted Answer

facultativ

Question 2

In viruses such as influenza,the ability to undergo a major genetic alteration is called

Accepted Answer

A)  antigenic drift. 
B)  antigenic shift. 
C)  antigenic variation. 
D)  antigenic binding. 
A)  antigenic drift. 
B)  antigenic shift. 
C)  antigenic variation. 
D)  antigenic binding.

Question 3

Protozoans use all the following mechanisms to avoid the host immune system EXCEPT

Accepted Answer

A)  antigenic variation. 
B)  toxin production. 
C)  antigenic masking. 
D)  intracellular location. 
A)  antigenic variation. 
B)  toxin production. 
C)  antigenic masking. 
D)  intracellular location.

Question 4

Which of the following protozoans uses antigenic variation to circumvent the host immune system?

Accepted Answer

A)  plasmodium 
B)  entamoeba 
C)  leishmania 
D)  trypanosome 
A)  plasmodium 
B)  entamoeba 
C)  leishmania 
D)  trypanosome

Question 5

Which of the following is an example of an obligate intracellular pathogen?

Accepted Answer

A)  Listeria monocytogenes 
B)  Shigella dysenteriae 
C)  Coxiella burnetii 
D)  Streptococcus pneumoniae 
A)  Listeria monocytogenes 
B)  Shigella dysenteriae 
C)  Coxiella burnetii 
D)  Streptococcus pneumoniae

Question 6

Using the figure below,explain how Salmonella enterica uses its type III secretion systems to invade the eukaryotic host cell and become an intracellular parasite.

Accepted Answer

Salmonella attaches to host M cells with

Question 7

Biofilm infections are important clinically because

Accepted Answer

A)  WBC easily penetrate biofilms. 
B)  bacteria in biofilms are more susceptible to antimicrobial compounds. 
C)  bacteria in biofilms can persist against host defenses. 
D)  bacteria in biofilms do not grown on medical devices. 
A)  WBC easily penetrate biofilms. 
B)  bacteria in biofilms are more susceptible to antimicrobial compounds. 
C)  bacteria in biofilms can persist against host defenses. 
D)  bacteria in biofilms do not grown on medical devices.

Question 8

What is the purpose of the actin-myosin motor shown in the figure below?

Accepted Answer

A)  The pathogen uses this structure to enter the host cell. 
B)  The pathogen uses this structure to produce toxins. 
C)  The pathogen uses this structure as a secretion apparatus. 
D)  The pathogen uses this structure to prevent phagocytosis. 
A)  The pathogen uses this structure to enter the host cell. 
B)  The pathogen uses this structure to produce toxins. 
C)  The pathogen uses this structure as a secretion apparatus. 
D)  The pathogen uses this structure to prevent phagocytosis.

Question 9

Which of the following is NOT an example of a bacterial secretion system that is paralogous to another molecular machine?

Accepted Answer

A)  type 1 protein secretion system 
B)  type II protein secretion system 
C)  type III protein secretion system 
D)  type IV protein secretion system 
A)  type 1 protein secretion system 
B)  type II protein secretion system 
C)  type III protein secretion system 
D)  type IV protein secretion system

Question 10

The purpose of the Tat protein in an HIV infection is to

Accepted Answer

A)  down regulate CD4 and MHC class 1 expression. 
B)  inhibit virus assembly. 
C)  accelerate HIV transcription by the host cell. 
D)  protect the cell from being killed by CD8 cytotoxic cells. 
A)  down regulate CD4 and MHC class 1 expression. 
B)  inhibit virus assembly. 
C)  accelerate HIV transcription by the host cell. 
D)  protect the cell from being killed by CD8 cytotoxic cells.

Question 11

Once a bacterium attaches and enters a host cell within a phagosome,the pathogen has one of three fates,depending on the pathogen.According to the figure below,Shigella and Listeria utilize which mechanism to avoid being destroyed by the host cell?

Accepted Answer

A)  survive inside the phagosome 
B)  escape from the phagosome 
C)  prevent phagosome-lysosome fusion 
D)  induce apoptosis 
A)  survive inside the phagosome 
B)  escape from the phagosome 
C)  prevent phagosome-lysosome fusion 
D)  induce apoptosis

Question 12

Antigenic drift occurs when

Accepted Answer

A)  two viruses infect the same cell. 
B)  a new viral strain is produced. 
C)  random mutations occur in the neuraminidase spike. 
D)  random mutations occur in the hemagglutinin spike. 
A)  two viruses infect the same cell. 
B)  a new viral strain is produced. 
C)  random mutations occur in the neuraminidase spike. 
D)  random mutations occur in the hemagglutinin spike.

Question 13

Explain the difference between antigenic drift and antigenic shift.How might antigenic shift relate to the generation of a new flu pandemic?

Accepted Answer

Antigenic drift is the accumulation of r

Question 14

Type I pili are different from type IV pili in that type I pili

Accepted Answer

A)  are static structures. 
B)  are thin and flexible. 
C)  allow for twitching motility. 
D)  are dynamic. 
A)  are static structures. 
B)  are thin and flexible. 
C)  allow for twitching motility. 
D)  are dynamic.

Question 15

Organisms such as Shigella and Listeria are able to move from cell to cell without being detected by the host immune system.What method are they using?

Accepted Answer

A)  production of an actin tail that propels them from cell to cell 
B)  production of a capsule to avoid antibody binding 
C)  production of protein A molecules to bind the Fc region of antibodies 
D)  production of proteins to trigger apoptosis in host cells 
A)  production of an actin tail that propels them from cell to cell 
B)  production of a capsule to avoid antibody binding 
C)  production of protein A molecules to bind the Fc region of antibodies 
D)  production of proteins to trigger apoptosis in host cells

Question 16

All of the following are exotoxins EXCEPT

Accepted Answer

A)  superantigens. 
B)  AB toxins. 
C)  plasma membrane disruption toxins. 
D)  lipopolysaccharide. 
A)  superantigens. 
B)  AB toxins. 
C)  plasma membrane disruption toxins. 
D)  lipopolysaccharide.

Question 17

All of the following statements about type III secretion systems are true EXCEPT

Accepted Answer

A)  proteins are injected directly into the eukaryotic cells. 
B)  type III secretion systems are evolutionarily related to flagellar genes. 
C)  cell-to-cell contact triggers type III secretion systems. 
D)  virulence proteins secreted by type III systems alter protein synthesis. 
A)  proteins are injected directly into the eukaryotic cells. 
B)  type III secretion systems are evolutionarily related to flagellar genes. 
C)  cell-to-cell contact triggers type III secretion systems. 
D)  virulence proteins secreted by type III systems alter protein synthesis.

Question 18

Label the figure below with where the Tetanus,Shiga,and Cholera toxins affect cellular function.

Accepted Answer

Tetanus toxin: affects host ce

Question 19

Cervical warts are caused by

Accepted Answer

A)  HBV. 
B)  HPV. 
C)  HIV. 
D)  herpes. 
A)  HBV. 
B)  HPV. 
C)  HIV. 
D)  herpes.

Question 20

Refer to the figure below.The secretion system displayed mirrors that of a pilus.Which secretion system is this?

Accepted Answer

A)  type I 
B)  type II 
C)  type III 
D)  type IV 
A)  type I 
B)  type II 
C)  type III 
D)  type IV

Exam 18: Microbial Pathogenesis

Organisms that can survive inside or outside host cells are called ________ pathogens.

In viruses such as influenza,the ability to undergo a major genetic alteration is called

Protozoans use all the following mechanisms to avoid the host immune system EXCEPT

Which of the following protozoans uses antigenic variation to circumvent the host immune system?

Which of the following is an example of an obligate intracellular pathogen?

Using the figure below,explain how Salmonella enterica uses its type III secretion systems to invade the eukaryotic host cell and become an intracellular parasite.

Biofilm infections are important clinically because

What is the purpose of the actin-myosin motor shown in the figure below?

Which of the following is NOT an example of a bacterial secretion system that is paralogous to another molecular machine?

The purpose of the Tat protein in an HIV infection is to

Once a bacterium attaches and enters a host cell within a phagosome,the pathogen has one of three fates,depending on the pathogen.According to the figure below,Shigella and Listeria utilize which mechanism to avoid being destroyed by the host cell?

Antigenic drift occurs when

Explain the difference between antigenic drift and antigenic shift.How might antigenic shift relate to the generation of a new flu pandemic?

Type I pili are different from type IV pili in that type I pili

Organisms such as Shigella and Listeria are able to move from cell to cell without being detected by the host immune system.What method are they using?

All of the following are exotoxins EXCEPT

All of the following statements about type III secretion systems are true EXCEPT

Label the figure below with where the Tetanus,Shiga,and Cholera toxins affect cellular function.

Cervical warts are caused by

Refer to the figure below.The secretion system displayed mirrors that of a pilus.Which secretion system is this?

Microbes Shape Our History

Basic Concepts of Infectious Disease

Observing Microbes

Living Chemistry: From Atoms to Cells

Cell Biology of Bacteria and Eukaryotes

Bacterial Growth, Nutrition, and Differentiation

Bacterial Metabolism

Bacterial Genetics and Biotechnology

Bacterial Genomes and Evolution

Bacterial Diversity

Eukaryotic Microbes and Invertebrate Infectious Agents

Viruses

Sterilization, Disinfection, and Antibiotic Therapy

Normal Human Microbiota: a Delicate Balance of Power

The Immune System: Inflammation and Innate Immunity

The Immune System: Adaptive Immunity

Immune Disorders, Tools, and Vaccines

Infections of the Skin and Eye

Infections of the Respiratory Tract

Systemic Infections

Infections of the Digestive System

Infections of the Urinary and Reproductive Tracts

Infections of the Central Nervous System

Diagnostic Clinical Microbiology

Epidemiology: Tracking Infectious Diseases

Environmental and Food Microbiology

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