THE MOLECULAR BASIS OF INHERITANCE
VIRUSES AND PRIONS
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Double-stranded DNA
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Single-stranded DNA
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Double-stranded RNA
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Single-stranded RNA
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Detailed explanation-1: -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-2: -Viroids are single-stranded covalently closed circular RNA molecules existing as highly base-paired rod-like structures.
Detailed explanation-3: -(ii) Viroids are single-stranded molecules.
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.
Detailed explanation-5: -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).