Match List-I with List-II:
| List-I | List-II |
|---|---|
| A. Plasmid | I. Virus infecting bacteria |
| B. Bacteriophage | II. Natural polymer extracted from sea weeds |
| C. Elution | III. Autonomously replicating circular extra-chromosomal DNA |
| D. Agarose | IV. Extraction of separated DNA bands from the gel piece |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → A-III, B-I, C-IV, D-II
(A) Plasmid — this matches (III) Autonomously replicating circular extra-chromosomal DNA. A plasmid lies outside the bacterial chromosome and copies itself on its own, which is why it is used as a vector.
(B) Bacteriophage — this matches (I) Virus infecting bacteria. Bacteriophages multiply inside bacterial cells and have a very high copy number of their genome there.
(C) Elution — this matches (IV) Extraction of separated DNA bands from the gel piece. After electrophoresis, the band of the wanted DNA is cut out of the gel and the DNA is extracted from it.
(D) Agarose — this matches (II) Natural polymer extracted from sea weeds. It is the matrix most commonly used for gel electrophoresis of DNA.
NCERT Extract:
Principles of Biotechnology – “… The construction of the first recombinant DNA emerged from the possibility of linking a gene encoding antibiotic resistance with a native plasmid (autonomously replicating circular extra-chromosomal DNA) of Salmonella typhimurium.”
Restriction Enzymes – “… Nowadays the most commonly used matrix is agarose which is a natural polymer extracted from sea weeds. … The separated bands of DNA are cut out from the agarose gel and extracted from the gel piece. This step is known as elution.”
Cloning Vectors – “You know that plasmids and bacteriophages have the ability to replicate within bacterial cells independent of the control of chromosomal DNA.”