Question

Match column I with column II, and choose the correct combination from the options given below.

	Column I		Column II
a.	Cloning vector	1.	Agrobacterium
b.	Ti-DNA	2.	pBR322
c.	Disarmed pathogen	3.	GAATTC
d.	Recognition sequence	4.	Transformation

• A. $a-3,b-4,c-1,d-2$
• B. $a-3,b-4,c-2,d-1$
• C. $a-2,b-1,c-3,d-4$
• D. $a-2,b-1,c-4,d-3$

Answer 1

The correct option is D $a-2,b-1,c-4,d-3$

Cloning vector - pBR322

Cloning vectors are the DNA molecules that can carry a foreign DNA fragment to be cloned. For example, pBR 322 is a cloning plasmid vector that is used to transfer a DNA of interest into a host cell such as Escherichia coli to form multiple copies.

Ti-DNA - Agrobacterium

Agrobacterium tumefaciens is a bacterial plant pathogen which carries the Ti plasmid or tumour inducing plasmid (extrachromosomal DNA). The T-DNA segment of the Ti plasmid integrates itself into the plant cell’s genome to induce tumour formation in plants.

Disarmed pathogen - Transformation

Disarmed pathogen is the method used for transferring the recombinant DNA into the host cells, like plant cells and animal cells. It is created by replacing the gene responsible for the pathogenic effect with the alien gene.

For example, Removing some genes from T-DNA will make Ti plasmid a vector for transferring genes in the plant cells. Disarmed retroviral vectors are used for transferring genes in animal cells.

Recognition sequence - GAATTC

Recognition sequences are the sites in a DNA where a restriction endonuclease can make a cut. GAATTC is a recognition sequence for the restriction enzyme EcoR I which cuts the DNA between G and A on both the strands.

Hence the correct option is
c. $a-2,b-1,c-4,d-3$