Question

Which of the following statements is TRUE regarding plasmids?

1) Certain types of plasmids called episomes can replicate independently of the main chromosome or insert themselves into the bacterial genome.
2) Plasmids are common in eukaryotes.
3) Plasmids often carry genes for antibiotic resistance.
4) Plasmids consist of single-stranded DNA.
5) More than one of the answers A-D are true.

Answer 1

The correct answer is statement 1 only, and statement 5 is false as well. Plasmids are small, circular, double-stranded DNA molecules found in prokaryotic cells. They can replicate independently of the main chromosome and often carry genes for antibiotic resistance.

Step-by-step explanation:

Plasmids are small, circular, double-stranded DNA molecules that are not part of the chromosome and can be found in prokaryotic cells, including bacteria. Certain types of plasmids, called episomes, can replicate independently of the main chromosome or insert themselves into the bacterial genome, making statement 1 true. Plasmids are not common in eukaryotes, so statement 2 is false.

However, plasmids often carry genes for antibiotic resistance, making statement 3 true. Plasmids consist of double-stranded DNA, not single-stranded DNA, so statement 4 is false. Therefore, the correct answer is statement 1 only, and statement 5 is false as well.