Consider the following statements:1. Adenoviruses have single stranded DNA genomes whereas retroviruses have double-stranded DNA genomes.2. Common cold is sometimes caused by an adenovirus whereas AIDS is caused by a retrovirus.Which of the statements given above is/are correct?
✓ Correct answer: b) 2 only
ExplanationAdenoviruses are non-enveloped, double-stranded DNA viruses that infect a wide range of hosts, including humans.They are known for their ability to efficiently infect various cell types.A retrovirus is a virus that uses RNA as its genetic material.Upon infection with a retrovirus, a cell converts the retroviral RNA into DNA, which in turn is inserted into the DNA of the host.Statement 1 is incorrect: Adenoviruses possess linear, double-stranded DNA genomes whereas retroviruses have single-stranded RNA genomes.Upon infecting a host cell, retroviruses use the enzyme reverse transcriptase to convert their RNA into double-stranded DNA, which is then integrated into the host’s genome.Statement 2 is correct: Adenoviruses are known to cause respiratory illnesses, including symptoms similar to the common cold.AIDS (Acquired Immunodeficiency Syndrome) is caused by the Human Immunodeficiency Virus (HIV), which is a retrovirus.49
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