Table of contents

1. Introduction to Microbiology3h 22m
2. Disproving Spontaneous Generation1h 18m
3. Chemical Principles of Microbiology3h 38m
4. Water1h 28m
5. Molecules of Microbiology2h 23m
6. Cell Membrane & Transport3h 28m
7. Prokaryotic Cell Structures & Functions5h 52m
8. Eukaryotic Cell Structures & Functions2h 18m
9. Microscopes2h 46m
10. Dynamics of Microbial Growth4h 36m
11. Controlling Microbial Growth4h 10m
12. Microbial Metabolism5h 16m
13. Photosynthesis2h 31m
14. DNA Replication2h 25m
15. Central Dogma & Gene Regulation7h 14m
16. Microbial Genetics4h 44m
17. Biotechnology3h 0m
18. Viruses, Viroids, & Prions4h 56m
19. Innate Immunity7h 15m
20. Adaptive Immunity7h 14m
21. Principles of Disease6h 57m

21. Principles of Disease

Molecular Koch's Postulates

Microbiology

21. Principles of Disease

Molecular Koch's Postulates

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Multiple Choice

Virulence factors include which of the following answers?

Toxins found in the outer-membrane of certain species of bacteria.

Bacterial capsules that allow the bacterium to evade phagocytosis by immune cells.

Proteins on the surface of a virus that allows the virus to bind to the host cell's surface.

A and B only.

All of the above.

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Verified step by step guidance

Understand the definition of virulence factors: Virulence factors are molecules produced by pathogens (bacteria, viruses, fungi, and protozoa) that contribute to the pathogenicity of the organism and enable them to achieve colonization, immunoevasion, and immunosuppression.

Analyze option A: Toxins found in the outer-membrane of certain species of bacteria are known as endotoxins, which are a type of virulence factor that can trigger strong immune responses.

Analyze option B: Bacterial capsules are polysaccharide layers that surround some bacteria, helping them evade phagocytosis by immune cells, thus acting as a virulence factor.

Analyze option C: Proteins on the surface of a virus that allow the virus to bind to the host cell's surface are known as viral attachment proteins, which are crucial for the virus to infect host cells and are considered virulence factors.

Conclude that all options (A, B, and C) describe mechanisms that enhance the ability of pathogens to cause disease, thus all are considered virulence factors.