Plasmids
Contain antibiotic resistance genes
Contain ds DNA molecule
Are self replicable
All the above

Options

A. Contain antibiotic resistance gens
B. Contain ds DNA molecule
C. Are self replicable
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding Plasmids:**
- Plasmids are small, circular, extra-chromosomal DNA molecules found in many bacteria and some eukaryotic cells. They are distinct from chromosomal DNA and can exist independently within the cell.

2. **Characteristics of Plasmids:**
- **Contain Antibiotic Resistance Genes:** Many plasmids carry genes that provide resistance to antibiotics, allowing bacteria to survive in the presence of these drugs. This is a significant feature that makes plasmids important in medical and biotechnological applications.
- **Contain Double-Stranded DNA (ds DNA):** Plasmids are composed of double-stranded DNA, which is the standard structure for DNA molecules. This means they have two complementary strands that form a helical structure.
- **Are Self-Replicating:** Plasmids have the ability to replicate independently of chromosomal DNA. This self-replication is crucial for their propagation within bacterial populations.

3. **Evaluating the Options:**
- Given the characteristics of plasmids, we can evaluate the provided options:
- **Contain antibiotic resistance genes:** True
- **Contain ds DNA molecule:** True
- **Are self-replicable:** True
- Since all the statements about plasmids are correct, the answer is "All the above."

4. **Conclusion:**
- Therefore, the correct answer to the question is "All the above."

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