Okay, everyone. What are prions? Okay. So we've been talking about viruses, viroids, and other infectious agents, and prions are going to be one of those other infectious agents. Now what are they? Answer choice a says mobile segments of DNA. Actually, no. They're not gonna be made of nucleic acids whatsoever. They're going to be made of proteins. Answer choice b says, tiny circular molecules of RNA that can infect plants. Remember, they're gonna be proteins. Answer choice b is specifically referring to viroids, but viroids are made of nucleic acids, specifically single stranded RNA, and prions are gonna be made of infectious proteins. So that's not true. Answer choice c says viral DNA that attaches itself to the host genome and causes disease. Again, it's not gonna be a nucleic acid. It's a protein. And perhaps, in answer choice c, they're talking about a latent virus that incorporates its genome into the host genome. But we're not talking about DNA or RNA. We are talking about proteins. Answer choice d says, mis folded versions of normal proteins that cause disease. Absolutely perfect. The correct answer here is answer choice d. Prions are pretty crazy because they are proteins that are incorrectly folded. And whenever they come in contact with other proteins, normal ones, they cause those normal proteins to misfold. And this is kind of a cascading event. When all of those proteins start to misfold, they can no longer function. And then this is going to result in some sort of disease in that particular organism because their proteins are no longer working. Okay, everyone. Let's move on to our next video.

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

18. Viruses, Viroids, & Prions

Prions

Microbiology

18. Viruses, Viroids, & Prions

Prions

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Multiple Choice

What are prions?

Mobile segments of DNA.

Tiny circular molecules of RNA that can infect plants.

Viral DNA that attaches itself to the host genome and causes disease.

Misfolded versions of normal proteins that can cause disease.

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Verified step by step guidance

Understand that prions are not living organisms like bacteria or viruses, but rather misfolded proteins.

Recognize that prions can induce other normal proteins in the brain to also misfold, leading to disease.

Note that prions are associated with neurodegenerative diseases such as Creutzfeldt-Jakob disease in humans and mad cow disease in cattle.

Differentiate prions from other infectious agents like viruses and bacteria, which contain nucleic acids (DNA or RNA) and can replicate independently.

Remember that prions are unique in that they do not contain genetic material and their infectious nature is due to their abnormal protein structure.