Principles of Inheritance and Variations — BIOLOGY STD 12 Science — Question

$I.$ Ethidium bromide

$II.$ Restriction endonuclease

$III.$ Agarose

$IV.$ $UV$ radiation

Choose the correct option:

$I.$ Recombinant $DNA$ technology popularly known as genetic engineering is a stream of biotechnology which deals with the manipulation of genetic material by man in vitro

$II. pBR322$ is the first artificial cloning vector developed in $1977$ by Boliver and Rodriquez from $E$. coli plasmid

$III.$ Restriction enzymes belong to a class of enzymes called nucleases

Which of the statements given above are correct?

Reason : Histones are of five major types $H_1,\,H_2A\,, H_2B,H_3$ and $H_4$ .