Question 70
1. Adenoviruses have single-stranded DNA genomes whereas retroviruses have double-stranded DNA genomes.
2. Common cold is sometime caused by an adenovirus whereas AIDS is caused by a retrovirus.
Which of the statements given above is/are correct?
AOptions
BSolution
Statement 1 is incorrect: Adenoviruses possess double-stranded DNA (dsDNA) genomes. Retroviruses, on the other hand, have single-stranded RNA (ssRNA) genomes. A defining characteristic of retroviruses is that they use an enzyme called reverse transcriptase to convert their RNA genome into DNA once they infect a host cell. This DNA is then integrated into the host's genome.
Statement 2 is correct: Adenoviruses are a common cause of respiratory illnesses, including some forms of the common cold, as well as conjunctivitis and gastroenteritis. AIDS (Acquired Immunodeficiency Syndrome) is caused by the Human Immunodeficiency Virus (HIV), which is a retrovirus.
CStrategy
For questions on viruses, focus on their basic classification (DNA vs. RNA viruses, single-stranded vs. double-stranded) and common diseases they cause. Pay attention to specific virus families like retroviruses and their unique replication mechanisms.
DSyllabus Analysis
This question falls under General Science (Biology), specifically Virology and Human Diseases.
EQuestion Analysis
Medium. Requires specific knowledge of viral genome types and common diseases caused by different viral families.