The term episome refers to a type of

Options

A. Plasmid
B. cell wall
C. Membrane
D. Gene

Answer

**Step-by-Step Solution:**

1. **Understanding the Term "Episome":**
- The term "episome" is often used in genetics and microbiology. It is important to know what it refers to in the context of cellular structures.

2. **Identifying the Characteristics of Episomes:**
- An episome is a type of extra-chromosomal DNA. This means it exists outside of the main chromosomal DNA within a cell.
- Episomes have the unique ability to replicate independently of chromosomal DNA.

3. **Relating Episomes to Plasmids:**
- Episomes are often considered a subclass of plasmids. Plasmids are also extra-chromosomal DNA that can replicate independently.
- Therefore, it can be concluded that episomes are a type of plasmid.

4. **Excluding Other Options:**
- The question provides other options: cell walls, membranes, and genes.
- Cell walls are structural components found in plant cells and bacteria, not related to episomes.
- Membranes refer to the lipid bilayer surrounding cells, which is also not related to episomes.
- Genes are sequences of DNA that code for proteins, but they do not encompass the definition of episomes.

5. **Final Conclusion:**
- Based on the characteristics and relationships discussed, the term "episome" refers to a type of plasmid.

**Final Answer:**
The term episome refers to a type of **plasmid**.

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