Question 1

Symptoms of protozoan and helminthic diseases are due to

Accepted Answer

A) tissue damage due to growth of the parasite on the tissues. 
B) waste products excreted by the parasite. 
C) products released from damaged tissues. 
D) tissue damage due to growth of the parasite on the tissues and waste products excreted by the parasite. 
E) tissue damage due to growth of the parasite on the tissues,waste products excreted by the parasite,and products released from damaged tissues. 
A) tissue damage due to growth of the parasite on the tissues. 
B) waste products excreted by the parasite. 
C) products released from damaged tissues. 
D) tissue damage due to growth of the parasite on the tissues and waste products excreted by the parasite. 
E) tissue damage due to growth of the parasite on the tissues,waste products excreted by the parasite,and products released from damaged tissues. E

Question 2

The ability of some microbes,such as Trypanosoma or Giardia to alter their surface molecules and evade destruction by the host's antibodies is called

Accepted Answer

A) antigenic variation. 
B) lysogenic conversion. 
C) virulence. 
D) cytopathic effect. 
E) cytocidal effect. 
A) antigenic variation. 
B) lysogenic conversion. 
C) virulence. 
D) cytopathic effect. 
E) cytocidal effect. A

Question 3

Patients developed inflammation a few hours following eye surgery.Instruments and solutions were sterile,and the Limulus assay was positive.The patients' inflammation was due to

Accepted Answer

A) bacterial infection. 
B) viral infection. 
C) endotoxin. 
D) exotoxin. 
E) The answer cannot be determined based on the information provided. 
A) bacterial infection. 
B) viral infection. 
C) endotoxin. 
D) exotoxin. 
E) The answer cannot be determined based on the information provided. C

Question 4

Some pathogens evade phagocytosis,while other pathogens evade host defenses by entering host cells.Discuss the advantages and disadvantages of both of these evasion strategies.

Accepted Answer

Some pathogens have evolved the ability

Question 5

Botulism is caused by ingestion of a proteinaceous exotoxin;therefore,it can easily be prevented by

Accepted Answer

A) boiling food prior to consumption. 
B) administering antibiotics to patients. 
C) not eating canned food. 
D) preventing fecal contamination of food. 
E) filtering food. 
A) boiling food prior to consumption. 
B) administering antibiotics to patients. 
C) not eating canned food. 
D) preventing fecal contamination of food. 
E) filtering food.

Question 6

In general,the LD₅₀ for exotoxins is much greater than the LD₅₀ for endotoxins.

Accepted Answer

A) True 
 B)False

Question 7

All of the following are examples of entry via the parenteral route EXCEPT

Accepted Answer

A) injection. 
B) bite. 
C) surgery. 
D) hair follicle. 
E) skin cut. 
A) injection. 
B) bite. 
C) surgery. 
D) hair follicle. 
E) skin cut.

Question 8

The fimbriae of Neisseria gonorrhea and enteropathogenic E.coli are examples of

Accepted Answer

A) adhesins. 
B) ligands. 
C) receptors. 
D) adhesins and ligands. 
E) adhesins,ligands,and receptors. 
A) adhesins. 
B) ligands. 
C) receptors. 
D) adhesins and ligands. 
E) adhesins,ligands,and receptors.

Question 9

Cytopathic effects,such as inclusion bodies and syncytium formation,are the visible signs of viral infections.

Accepted Answer

A) True 
 B)False

Question 10

Which of the following statements about exotoxins is generally FALSE?

Accepted Answer

A) They are more potent than endotoxins. 
B) They are composed of proteins. 
C) They are resistant to heat. 
D) They have specific methods of action. 
E) They are produced by gram-positive bacteria. 
A) They are more potent than endotoxins. 
B) They are composed of proteins. 
C) They are resistant to heat. 
D) They have specific methods of action. 
E) They are produced by gram-positive bacteria.

Question 11

Which of the following statements about staphylococcal enterotoxin is FALSE?

Accepted Answer

A) It causes vomiting. 
B) It causes diarrhea. 
C) It is an exotoxin. 
D) It is produced by Staphylococcus aureus growing in the host's intestines. 
E) It is a superantigen. 
A) It causes vomiting. 
B) It causes diarrhea. 
C) It is an exotoxin. 
D) It is produced by Staphylococcus aureus growing in the host's intestines. 
E) It is a superantigen.

Question 12

All of the following are methods of avoiding host antibodies EXCEPT

Accepted Answer

A) antigenic changes. 
B) IgA proteases. 
C) invasins. 
D) membrane-disrupting toxins. 
E) inducing endocytosis. 
A) antigenic changes. 
B) IgA proteases. 
C) invasins. 
D) membrane-disrupting toxins. 
E) inducing endocytosis.

Question 13

Bacteria that cause periodontal disease have adhesins for receptors on streptococci that colonize on teeth.This indicates that

Accepted Answer

A) streptococci get bacterial infections. 
B) streptococcal colonization is necessary for periodontal disease. 
C) bacteria that cause periodontal disease adhere to gums and teeth. 
D) bacteria that cause periodontal disease adhere to teeth. 
E) streptococci cause periodontal disease. 
A) streptococci get bacterial infections. 
B) streptococcal colonization is necessary for periodontal disease. 
C) bacteria that cause periodontal disease adhere to gums and teeth. 
D) bacteria that cause periodontal disease adhere to teeth. 
E) streptococci cause periodontal disease.

Question 14

Which disease-associated fungi or fungal characteristics are mismatched?

Accepted Answer

A) ergot - sclerotia 
B) trichothecenes - inhibit protein synthesis 
C) Cryptococcus neoformans - capsules 
D) Claviceps purpura - aflatoxin 
E) Amantia - neurotoxin 
A) ergot - sclerotia 
B) trichothecenes - inhibit protein synthesis 
C) Cryptococcus neoformans - capsules 
D) Claviceps purpura - aflatoxin 
E) Amantia - neurotoxin

Question 15

All of the following bacteria release endotoxin EXCEPT

Accepted Answer

A) Clostridium botulinum. 
B) Salmonella Typhi. 
C) Neisseria meningitidis. 
D) Proteus vulgaris. 
E) Haemophilus influenzae. 
A) Clostridium botulinum. 
B) Salmonella Typhi. 
C) Neisseria meningitidis. 
D) Proteus vulgaris. 
E) Haemophilus influenzae.

Question 16

The best description of direct damage by a pathogen is

Accepted Answer

A) host cells destroyed when pathogens metabolize and multiply. 
B) capsule components of pathogens kill cells. 
C) poisonous substances secreted by viruses kill cells. 
D) superantigens cause cytokine release which then cause symptoms of disease. 
E) protein synthesis is interrupted by toxins. 
A) host cells destroyed when pathogens metabolize and multiply. 
B) capsule components of pathogens kill cells. 
C) poisonous substances secreted by viruses kill cells. 
D) superantigens cause cytokine release which then cause symptoms of disease. 
E) protein synthesis is interrupted by toxins.

Question 17

The Limulus amoebocyte assay is used to detect minute amounts of endotoxin in drugs and medical devices.

Accepted Answer

A) True 
 B)False

Question 18

Endotoxins are

Accepted Answer

A) associated with gram-positive bacteria. 
B) molecules that bind nerve cells. 
C) part of the gram-negative cell wall. 
D) excreted from the cell. 
E) A-B toxins. 
A) associated with gram-positive bacteria. 
B) molecules that bind nerve cells. 
C) part of the gram-negative cell wall. 
D) excreted from the cell. 
E) A-B toxins.

Question 19

Table 15.2
 $$\begin{array} { | l | c | } 
\hline \text { Bacterium } & \text { ID50 } \
\hline \text { E. coli } \mathrm { O } 157 : \mathrm { H } 7 & 20 \
\hline \text { Legionella pneumophila } & 1 \
\hline \text { Shigella } & 10 \
\hline \text { Treponema pallidum } & 57 \
\hline
\end{array}$$
-Which organism in Table 15.2 most easily causes an infection?

Accepted Answer

A) 
E) coli O157:H7 
B) Legionella pneumophila 
C) Shigella 
D) Treponema pallidum 
E) The answer cannot be determined based on the information provided. 
A) 
E) coli O157:H7 
B) Legionella pneumophila 
C) Shigella 
D) Treponema pallidum 
E) The answer cannot be determined based on the information provided.

Question 20

Biofilms provide pathogens with an adhesion mechanism and aid in resistance to antimicrobial agents.

Accepted Answer

A) True 
 B)False

Exam 15: Microbial Mechanisms of Pathogenicity

Symptoms of protozoan and helminthic diseases are due to

The ability of some microbes,such as Trypanosoma or Giardia to alter their surface molecules and evade destruction by the host's antibodies is called

Patients developed inflammation a few hours following eye surgery.Instruments and solutions were sterile,and the Limulus assay was positive.The patients' inflammation was due to

Some pathogens evade phagocytosis,while other pathogens evade host defenses by entering host cells.Discuss the advantages and disadvantages of both of these evasion strategies.

Botulism is caused by ingestion of a proteinaceous exotoxin;therefore,it can easily be prevented by

In general,the LD₅₀ for exotoxins is much greater than the LD₅₀ for endotoxins.

All of the following are examples of entry via the parenteral route EXCEPT

The fimbriae of Neisseria gonorrhea and enteropathogenic E.coli are examples of

Cytopathic effects,such as inclusion bodies and syncytium formation,are the visible signs of viral infections.

Which of the following statements about exotoxins is generally FALSE?

Which of the following statements about staphylococcal enterotoxin is FALSE?

All of the following are methods of avoiding host antibodies EXCEPT

Bacteria that cause periodontal disease have adhesins for receptors on streptococci that colonize on teeth.This indicates that

Which disease-associated fungi or fungal characteristics are mismatched?

All of the following bacteria release endotoxin EXCEPT

The best description of direct damage by a pathogen is

The Limulus amoebocyte assay is used to detect minute amounts of endotoxin in drugs and medical devices.

Endotoxins are

Table 15.2 Bacterium ID50 E. coli 157:7 20 Legionella pneumophila 1 Shigella 10 Treponema pallidum 57 -Which organism in Table 15.2 most easily causes an infection?

Biofilms provide pathogens with an adhesion mechanism and aid in resistance to antimicrobial agents.

The Microbial World and You

Chemical Principles

Observing Microorganisms Through a Microscope

Functional Anatomy of Prokaryotic and Eukaryotic

Microbial Metabolism

Microbial Growth

The Control of Microbial Growth

Microbial Genetics

Biotechnology and Dna Technology

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

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

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