Q. In genetic engineering, a DNA segment (gene) of interest, is transferred to the host cell through a vector. Consider the following four agents (I-IV) in this regard and select the correct option about which one or more of these can be used as a vector/vectors I. Bacterium II. Plasmid III. $Plasmodium$ IV. Bacteriophage
A) I, II and IV
B) I only
C) I and III
D) II and IV
Explanation
Circular plasmid DNA which is used as a vector, can be cleaved at one site with the help of enzyme to give a linear DNA molecule. A foreign DNA segment can now be inserted, by joining the ends of broken circular DNA to the two ends of foreign DNA, thus regenerating a bigger circular DNA molecule that can now be separated by gel electrophoresis on the basis of its size Bacteriophages provide another source of cloning vectors. Since, usually, a phage has a linear DNA molecule, a single break will generate two fragments, which are later joined together with foreign DNA to generate a chimeric phage particle
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.