Question

Viruses have :

• A. Prokaryotic nucleus
• B. Single chromosome
• C. Both DNA and RNA
• D. DNA enclosed in a protein coat

Answer 1

The Correct Option is D

To determine the correct answer to the question about the characteristics of viruses, let's evaluate each option:

1. Prokaryotic nucleus: Viruses do not have a prokaryotic nucleus. In fact, viruses are acellular and do not possess any true cellular structure like nuclei, organelles, or cytoplasm. Prokaryotic implies a cellular organism without a true nucleus, such as bacteria.
2. Single chromosome: Viruses do not have chromosomes as found in cellular organisms. They contain either DNA or RNA in a form that is much simpler than a chromosome, often as a single molecule that operates differently than cellular DNA.
3. Both DNA and RNA: Viruses do not have both DNA and RNA. A virus will contain either DNA or RNA, never both simultaneously. This is one of the key distinctions of viral genetic material.
4. DNA enclosed in a protein coat: This is a characteristic feature of many viruses. Viruses contain genetic material (either DNA or RNA, not both) that is enclosed within a protective protein coat known as a capsid. This structure allows viruses to infect host cells and is essential to their transmission and survival.

By reviewing these options, we conclude that the correct answer is DNA enclosed in a protein coat. This encapsulation allows viruses to protect their genetic material and facilitates their transmission by means of infecting host organisms.

This understanding is crucial as it helps distinguish viruses from other microorganisms and highlights the unique manner in which they operate and cause infections.