BIOLOGICAL CLASSIFICATION
KINGDOM MONERA
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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DNA is not present at any stage in the life cycle of retroviruses
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Retroviruses carry gene for RNA dependent DNA polymerase
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The genetic material in mature retroviruses is RNA
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Retroviruses are causative agents for certain kinds of cancer in man
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Detailed explanation-1: -So, the correct answer is option (D), DNA is not present at any stage in the life cycle of retroviruses.
Detailed explanation-2: -So, the correct answer is ‘An RNA virus that can synthesise DNA during infection. ‘
Detailed explanation-3: -Retroviruses carry their genome as RNA, and because they replicate via a DNA intermediate, they must also carry the sequence for the promoter that will drive the expression of the genomic RNA.
Detailed explanation-4: -All retroviruses are protein-enveloped, positive-stranded RNA viruses that encode a unique enzyme, RT, capable of catalyzing the flow of genetic information from RNA to DNA, counter to that of most biologic systems.
Detailed explanation-5: -What molecule would you not expect to find in a retrovirus? Explanation: Retroviruses carry RNA and when they infect a host cell, they use their own reverse transciptase to made DNA from that RNA; therefore, within the virus, there are only the molecules that make up RNA.