Which of the following viruses possesses DNA a capsid with icosahedral symmetry and no lipid envelope
**Core Concept**
The question is testing the student's knowledge of viral structure, specifically the characteristics of viruses with DNA genomes. Viruses can be classified based on their genetic material (DNA or RNA), capsid structure (icosahedral or helical), and envelope presence (lipid or non-lipid).
**Why the Correct Answer is Right**
The correct answer is a virus with a DNA genome, icosahedral capsid symmetry, and no lipid envelope. These characteristics are typical of the family Poxviridae, which includes viruses such as the smallpox virus. Poxviruses have a large, complex genome and a unique structure that distinguishes them from other viruses.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not possess the characteristics mentioned in the question. For example, the herpesvirus family has a DNA genome and a lipid envelope.
* **Option B:** This option is incorrect because it has a different capsid symmetry and/or a lipid envelope. For example, the adenovirus family has a DNA genome and an icosahedral capsid, but also has a lipid envelope.
* **Option C:** This option is incorrect because it may have a different genetic material or capsid structure. For example, the influenza virus has an RNA genome and a lipid envelope.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that viral structure and classification are crucial for understanding viral replication, transmission, and pathogenesis. Familiarizing yourself with the characteristics of different viral families can help you diagnose and manage viral infections more effectively.
**Correct Answer: C. A poxvirus, such as the smallpox virus, is a correct example of a virus with a DNA genome, icosahedral capsid symmetry, and no lipid envelope.**