Virus envelope is known as

Options

A. Core
B. Capsid
C. Virion
D. Nucleoprotein

Answer

**Step-by-Step Solution:**

1. **Understanding Virus Structure**:
- A virus is composed of several key components, including nucleic acid (DNA or RNA), a protein coat, and sometimes an outer envelope.

2. **Identifying the Core**:
- The core of the virus refers to its nucleic acid content, which can be either DNA or RNA. This is not the envelope.

3. **Defining the Capsid**:
- The capsid is the protein coat that encases the viral nucleic acid. It is essential for protecting the genetic material and facilitating the infection of host cells.

4. **Exploring the Envelope**:
- The envelope of a virus is an outer layer that surrounds the capsid. This envelope is typically composed of lipids and carbohydrates derived from the host cell membrane.

5. **Clarifying Other Terms**:
- The term "virion" refers to the complete virus particle, which includes the nucleic acid, capsid, and any envelope if present.
- "Nucleoprotein" refers to the proteins associated with the nucleic acid within the virus, but does not refer to the envelope itself.

6. **Conclusion**:
- Based on the definitions and roles of these components, the virus envelope is best described as the capsid, which is the protein coat that also includes the surrounding lipid layer derived from the host.

**Final Answer**: The virus envelope is known as the **capsid**.

---