What is ‘Ori’? State its importance during cloning of a vector.

OR

Explain the importance of ‘selectable marker’, with the help of a suitableexample.

Ori or Origin of replication in a chromosome is responsible for the initiation of replication

Any segment or fragment of DNA, when linked with Ori region can replicate and can multiply itself into host organism, this is called cloning of a vector

It is responsible for controlling the copy number of the linked DNA

OR

Selectable marker is required to maintain the plasmid (small, circular, double stranded DNA molecule that can replicate independently of the chromosomes) in the cell

It helps in identifying and eliminating non transformants