Question

What is the difference between viroids and prions?

Answer 1

Hint: Plant pathogens are microscopic, circular, single-stranded particles known as viroids. They do not contribute to protein synthesis, although they are essential secondary structures. They are made up entirely of nucleic acid and have no protein.
Prion is an aberrant or misfolded protein that causes fatal sickness in animals and humans by infecting normal variations of the same protein with its misfolded structure.

Complete answer:

VIROIDS	PRIONS
Viroids are the tiniest infectious pathogens, consisting only of a single strand of circular, single-stranded self-replicating RNA with no protein coating.	Prion is an aberrant or misfolded protein that causes fatal sickness in animals and humans by infecting normal variations of the same protein with its misfolded structure.
It is an infectious RNA particle	It is an infectious protein particle.
It's made up entirely of single-stranded circular RNA.	It is only composed of Protein.
Nucleic acid is present.	Nucleic acid is absent.
Protein coat is absent.	Protein coat is not known.
Viroids are inactivated by ribonuclease digestion.	Proteinase K and trypsin digestion inactivate prions.
Resistant to proteinase K and trypsin digestion	Resistant to ribonuclease treatment.
Viroids are smaller than virus	Smaller than viroids.
Viroid infects only higher plants (Exception: hepatitis D virus in humans is similar to viroid)	Prions infect animals causing neurological degenerative diseases
Example: Potato Spindle Tuber Disease and Chrysanthemum Stunt Disease are two common plant diseases.	Examples: Mad cow disease in cows and Scrapie disease in sheep and goat, Creutzfeldt-Jakob Disease (CJD), Kuru.

Note:
Human disease is not caused by viruses. They are the ones to blame for crop disasters. Tomatoes, potatoes, coconut palms, and other plants are affected by viroids. Viruses include only RNA molecules that do not coat protein, whereas RNA or DNA molecules are wrapped within a protein coat in viruses. Viroids are secondary structures that don't have any proteins in them.