EVERYDAY SCIENCE

Detailed explanation-1: -Viroids are single-stranded, covalently closed circular RNA molecules. As a distinct class of pathogens, they are clearly distinguished from viruses by their small size (∼250–400 nt), do not encode any protein and lack a capsid.

Detailed explanation-2: -Viroids are infectious agents that consist only of naked RNA without any protective layer such as a protein coat. Viroids infect plants (but no other forms of life) and are replicated at the expense of the host cell. Viroid genomes are small single-stranded circles of RNA that are only 250–400 bases long.

Detailed explanation-3: -Viroids cause a variety of plant diseases, including potato spindle tuber disease, apple fruit crinkle, chrysanthemum stunt, and others. Thus, Viroids do not have DNA, they have RNA as their genetic material.

Detailed explanation-4: -Viroids are small and infectious RNA particles that do not code for proteins. They do not possess the protein coat. They are known to infect the plants.

Detailed explanation-5: -Viroids are single-stranded, circular, and noncoding RNAs that infect plants. They replicate in the nucleus or chloroplast and then traffic cell-to-cell through plasmodesmata and long distance through the phloem to establish systemic infection. They also cause diseases in certain hosts.