Question

Which of the following statements is not true regarding plasmids?

• A. Plasmids are small, extra-chromosomal DNA molecules commonly found only in bacteria.
• B. Plasmids can replicate independently of the cell they reside in.
• C. Plasmids are clones of bacterial chromosomes.
• D. Plasmids can be passed horizontally through processes called transformation, transduction, and conjugation.

Answer 1

Answer: (C)

Plasmids are clones of bacterial chromosomes.

Plasmids are extrachromosomal genetic material that confer certain additional properties to the bacterial cell in which they are present, like drug resistance, fertility factor, production of toxins etc. These are not required for the regular metabolic processes of the bacterial cell. Meaning they are genetically different from the bacterial chromosome.

So, the correct answer is 'Plasmids are clones of bacterial chromosomes.'