Define selectable marker.

Describe briefly : Selectable marker.

What do you understand by the term selectable marker?

Name and explain the role of a selectable marker in the vector pBR322.

Mention the role of selectable marker in facilitating recombinant DNA technology.

Why is the coding sequence of enzyme beta -galactosidase a preferred selectable marker in comparison to coated plate method?

Can you think and answer , how a reporter enzyme can be used to monitor transformation of host by foreign DNA in addition to selectable marker?

Define speed.

Why is it necessary to have 'selectable marker'in a cloning vector?