Read the following five statements in context of a plasmid. (a) Its DNA is always double stranded. (b) Its DNA is naked and without histone proteins. (c) Its DNA can replicate independent of genomic DNA. (d) Both exons and introns are present in plasmid DNA. (e) Plasmid DNA can be either linear or circular. Which of the above given statements are incorrect?

Options

A. (a) and (e)
B. (c) and (e)
C. (a), (b) and (c)
D. (d) and (e)

Answer

To determine which of the statements about plasmids are incorrect, let's analyze each statement step by step.

### Step-by-Step Solution:

1. **Statement (a): Its DNA is always double stranded.**
- Plasmids are typically double-stranded DNA (dsDNA) molecules. This statement is **true**.

2. **Statement (b): Its DNA is naked and without histone proteins.**
- Plasmid DNA is not associated with histone proteins, making it "naked". This statement is **true**.

3. **Statement (c): Its DNA can replicate independent of genomic DNA.**
- Plasmids have the ability to replicate independently of the host's genomic DNA. This statement is **true**.

4. **Statement (d): Both exons and introns are present in plasmid DNA.**
- Plasmids generally do not contain introns; they mainly consist of coding sequences (exons). This statement is **false**.

5. **Statement (e): Plasmid DNA can be either linear or circular.**
- Plasmids are predominantly circular DNA molecules. While some plasmids can be linear, the majority are circular, making this statement **false**.

### Conclusion:
The incorrect statements are **(d)** and **(e)**.

### Summary of Incorrect Statements:
- **(d)**: Plasmid DNA does not contain introns.
- **(e)**: Plasmid DNA is primarily circular, not linear.