Paper 2 · Genetic Engineering
Bacterial plasmids are
Aprotein coats that surround and protect the bacterial genetic material
Bfolded regions of the cell surface membrane on which respiration occurs
Csmall circular pieces of DNA separate from the main bacterial chromosome
Dshort lengths of messenger RNA copied from the main bacterial chromosome
Explanation: A plasmid is a small loop of double stranded DNA that replicates independently of the main bacterial chromosome. Because it can be taken up and copied by a bacterium, it makes a convenient vector for carrying a foreign gene into the cell.
Derived from ZIMSEC Biology Paper 2, Nov 2004, Q3