Question

Match the following:
$\begin{array}{cc}\text{Column I}& \text{Column II}\\ \text{A. Vector}& \text{i. Molecular scissors}\\ \text{B. DNA ligase}& \text{ii. Carrier}\\ \text{C. Host}& \text{iii. Molecular glue}\\ \text{D. Restriction enzymes}& \text{iv. Bacterial cell}\end{array}$

• A. A - ii, B - i, C - iv, D - iii
• B. A - ii, B - i, C - iii, D - iv
• C. A - ii, B - iii, C - iv, D - i
• D. A - i, B - ii, C - iii, D - iv

Answer 1

The correct option is C A - ii, B - iii, C - iv, D - i

In rDNA technology, a vector is any vehicle or carrier (usually a virus or a plasmid) that is used to carry a desired DNA sequence into a host cell as a part of a molecular cloning procedure. One of the most commonly used host organism in rDNA technology is a bacterium.

Ligases are enzymes that are capable of catalysing the reaction of joining two large molecules by establishing a new chemical bond. DNA ligase catalyses the joining of the 3′-OH to the 5′-phosphate, by forming a phosphodiester bond between two successive nucleotides. Hence, DNA ligase is also called molecular glue.

Nucleases are a broad and diverse class of enzymes that hydrolyse the phosphodiester bonds of DNA and RNA.

Endonucleases are a type of nucleases that cleave the phosphodiester bonds between consecutive nucleotides found within a polynucleotide. Restriction enzymes are a type of endonuclease. Restriction enzymes are called molecular scissors as they cleave DNA at or close to specific sequences known as restriction sites. These enzymes make a single incision on each of the two DNA strands and are also called restriction endonucleases.

Hence the correct answer would be
A - ii, B - iii, C - iv, D - i.