BIOLOGICAL CLASSIFICATION
VIRUSES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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bacterium
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viroid
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prion
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virus
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Detailed explanation-1: -Viroids are infectious agents composed solely of circular single-stranded RNA which folds over on itself to form some double stranded regions. These are catalytic RNAs (ribozymes).
Detailed explanation-2: -Although viroids are composed of nucleic acid, they do not code for any protein. The viroid’s replication mechanism uses RNA polymerase II, a host cell enzyme normally associated with synthesis of messenger RNA from DNA, which instead catalyzes “rolling circle” synthesis of new RNA using the viroid’s RNA as a template.
Detailed explanation-3: -Common viroid examples include: Potato spindle tuber viroid. Tomato planta macho viroid. Avocado sunblotch viroid.
Detailed explanation-4: -Viroids are small single-stranded RNA. Viroids are devoid of proteins. They cause various diseases in plants like the potato spindle tuber disease.