Which of the following is not a feature of the plasmids?
Answer: (D) Single – stranded. Answer: (D) Single – stranded Solution: Plasmids are small circular DNA molecules present outside the genomic DNA in many bacteria; like all DNA they are double-stranded, not single-stranded, so this is not a feature.
- A.Independent replication
- B.Circular structure
- C.Transferable
- D.Single – stranded✓
Correct Answer
(D) Single – stranded
Solution & Explanation
Answer: (D) Single – stranded Solution: Plasmids are small circular DNA molecules present outside the genomic DNA in many bacteria; like all DNA they are double-stranded, not single-stranded, so this is not a feature. Plasmids replicate independently, are circular, and can be transferred (used to monitor bacterial transformation with foreign DNA), making options 1, 2 and 3 valid features. Hence the odd one out is "single-stranded." NCERT Reference: Ch 8, p.90, lines 10–16: "many bacteria have small circular DNA outside the genomic DNA. These smaller DNA are called plasmids. The plasmid DNA confers certain unique phenotypic characters to such bacteria."
