Question

1. what is a prion, and how does it cause disease? a) a misfolded protein that causes other proteins to misfold b) a virus that only infects plants c) a bacterial toxin that causes paralysis d) a single - stranded rna molecule that replicates in human cells 6) how do viroids differ from viruses? a) viroids contain both dna and rna, while viruses contain only dna b) viroids lack a protein coat and only infect plants c) viroids cause diseases in animals, while viruses only infect plants d) viroids are more complex than viruses 7) which of the following is not a common way to classify viruses? a) type of genetic material (dna or rna) b) shape of the viral capsid c) presence or absence of a nucleus d) method of replication

Explanation:

• For question 5, prions are misfolded proteins that can induce other proteins to misfold, leading to disease.
• For question 6, viroids lack a protein - coat and mainly infect plants, which differentiates them from viruses.
• For question 7, viruses are acellular and do not have a nucleus, so the presence or absence of a nucleus is not a way to classify them.

Answer:

1. A. A misfolded protein that causes other proteins to misfold
2. B. Viroids lack a protein coat and only infect plants
3. C. Presence or absence of a nucleus