Question

Which of the following statements is/are true about plasmids? (Mark all correct responses.)

a. Plasmids are circular and "supercoiled" pieces of DNA that are found in bacteria
b. When a plasmid is cut at only one location by a restriction enzyme, the result is a linear, double-stranded piece of DNA that is the same size as the plasmid
c. Restriction enzymes can cut plasmid DNA at specific nucleotide sequences Plasmids, like all DNA, are composed of double strands of DNA

Answer 1

Answer: A, B and C

Step-by-step explanation:

Plasmids are small circular double-stranded DNA molecules found inside in the cytoplasm of bacterial cell.

Plasmids DNA are tightly supercoiled, also plasmid DNA are capable of replicating independent of the chromosomal DNA.

Since plasmid DNA are circular, supercoil and double stranded, when subjected to a restriction enzyme (such as Echo R1 or Hind III among others) the cut the plasmid DNA at specific restriction sites and a linear conformation of plasmid DNA is formed.

Example. The restriction site of Eco R1 is G AATTC and CTTAA G for both strands