Exam 25: Microbial Pathogenesis

Two Streptococcus pneumoniae strains, agent 1 and agent 2, are administered to groups of animals at different doses. Mortality rates are then measured for the animals that received each dose level of each agent. Agent 1 is found to have an LD₅₀ of 400. Agent 2 is found to have an LD₅₀ of 600. Which one is producing a capsule and which one is not? How do you know?

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Question 1

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Agent 1 (strain 1) is producing a capsule; agent 2 (strain 2) is not. Capsules make bacteria more virulent and thereby have a lower LD₅₀.

Synthesis of flagella and pili filaments in Gram-negatives share which of the following attributes?

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Question 2

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Agent A has an LD₅₀ of 400. Agent B has an LD₅₀ of 600. Which is the more pathogenic agent, A or B? What is the relationship between this measure and microbial virulence?

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Question 3

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Agent A is more virulent than agent B. Virulence is a measure of the severity or intensity of the disease-causing capacity of an organism. A low LD₅₀ would mean that relatively few numbers of the microbe will kill 50% of test animals. Such an organism will be regarded as highly virulent. Such organisms may possess capsules or other mechanisms of subverting or evading the host defenses. Similarly, organisms with high LD₅₀ are considered as having low virulence.

Which of the following does NOT result from the release of endotoxin from Gram-negative bacteria?

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Question 4

A life-threatening lung infection caused by biofilm formation in cystic fibrosis patients is

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Question 5

Which of the following species causes whooping cough?

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Question 6

Which of the following protein secretory systems injects effector molecules directly from the bacterial cytoplasm into the host cytoplasm?

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Question 7

Which of the following produces a toxin that disrupts protein synthesis?

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Question 8

Type I and Type IV pili both

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Question 9

Type IV pili are essential for the interaction of Neisseria meningitidis with brain endothelial cells. Describe the difference between the type IV and type I pili binding, and explain why knowing the type of binding is important in pathogenesis.

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Question 10

There is no host cell receptor for the enteropathogenic Escherichia coli intimin adhesion. How does this pathogen successfully colonize human intestines?

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Question 11

Protein A helps Staphylococcus aureus avoid

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Question 12

Multivalent adhesion molecule 7, or MAM7, is a unique adhesion because it

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Question 13

How does a pathogenicity island increase the "fitness" of a microorganism (pathogen) to interact with a host and cause disease?

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Question 14

Which of the following statements is NOT correct about a patient who died from endotoxin pathologies?

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Question 15

Yellow fever and West Nile virus are both

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Question 16

Bacteria that exhibit antigenic shifts and phase variations will most likely cause

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Question 17

Toxins with ADP ribosyltransferase activity cause

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Question 18

Which of the following techniques would be used to identify unknown virulence genes that are only expressed in the host?

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Question 19

The term used to designate how many bacteria or viruses are required to kill 50% of an experimental group of hosts is

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Question 20

Showing 1 - 20 of 70

Exam 25: Microbial Pathogenesis

Synthesis of flagella and pili filaments in Gram-negatives share which of the following attributes?

Agent A has an LD₅₀ of 400. Agent B has an LD₅₀ of 600. Which is the more pathogenic agent, A or B? What is the relationship between this measure and microbial virulence?

Which of the following does NOT result from the release of endotoxin from Gram-negative bacteria?

A life-threatening lung infection caused by biofilm formation in cystic fibrosis patients is

Which of the following species causes whooping cough?

Which of the following protein secretory systems injects effector molecules directly from the bacterial cytoplasm into the host cytoplasm?

Which of the following produces a toxin that disrupts protein synthesis?

Type I and Type IV pili both

Type IV pili are essential for the interaction of Neisseria meningitidis with brain endothelial cells. Describe the difference between the type IV and type I pili binding, and explain why knowing the type of binding is important in pathogenesis.

There is no host cell receptor for the enteropathogenic Escherichia coli intimin adhesion. How does this pathogen successfully colonize human intestines?

Protein A helps Staphylococcus aureus avoid

Multivalent adhesion molecule 7, or MAM7, is a unique adhesion because it

How does a pathogenicity island increase the "fitness" of a microorganism (pathogen) to interact with a host and cause disease?

Which of the following statements is NOT correct about a patient who died from endotoxin pathologies?

Yellow fever and West Nile virus are both

Bacteria that exhibit antigenic shifts and phase variations will most likely cause

Toxins with ADP ribosyltransferase activity cause

Which of the following techniques would be used to identify unknown virulence genes that are only expressed in the host?

The term used to designate how many bacteria or viruses are required to kill 50% of an experimental group of hosts is

Microbial Life: Origin and Discovery

Observing the Microbial Cell

Cell Structure and Function

Bacterial Culture, Growth, and Development

Environmental Influences and Control of Microbial Growth

Viruses

Genomes and Chromosomes

Transcription, Translation, and Bioinformatics

Gene Transfer, Mutations, and Genome Evolution

Molecular Regulation

Viral Molecular Biology

Biotechniques and Synthetic Biology

Energetics and Catabolism

Electron Flow in Organotrophy, Lithotrophy, and Phototrophy

Biosynthesis

Food and Industrial Microbiology

Origins and Evolution

Bacterial Diversity

Archaeal Diversity

Eukaryotic Diversity

Microbial Ecology

Microbes in Global Elemental Cycles

Human Microbiota and Innate Immunity

The Adaptive Immune Response

Microbial Diseases

Antimicrobial Therapy

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