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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

19. Innate Immunity

First-Line Defenses: Chemical Barriers

Microbiology

19. Innate Immunity

First-Line Defenses: Chemical Barriers

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Multiple Choice

Which of the following statements about the defensive roles of saliva and gastric juices are true?

Saliva's main function is to move microbes through and out of the gastrointestinal system.

Saliva possesses enzymes that inhibit microbial growth and digest microbes.

Gastric juice's main function is to destroy microbes and toxins eaten by the host.

Gastric juice is incredibly acidic which breaks down most pathogens.

All of the above are true statements.

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Verified step by step guidance

Understand the role of saliva in the gastrointestinal system. Saliva helps in the mechanical movement of food and microbes through the system, aiding in their removal.

Recognize the enzymatic properties of saliva. Saliva contains enzymes like lysozyme that can inhibit microbial growth and help in digesting microbes.

Examine the function of gastric juice in the stomach. Gastric juice is primarily responsible for destroying microbes and toxins that are ingested.

Consider the acidity of gastric juice. Gastric juice is highly acidic, with a pH around 1.5 to 3.5, which is effective in breaking down most pathogens.

Evaluate each statement based on the above understanding. All statements accurately describe the defensive roles of saliva and gastric juices in the human body.