Question

Mention any two methods of introducing alien DNA into the host.

Answer 1

• Recombinant DNA and the bacterial cells are incubated in ice, followed by placing them briefly at 42°C (heat shock) and then putting them back in ice. 
• By micro injection the recombinant DNA directly injected into the nucleus of the animal cell. 
• Plant cells are bombarded with high velocity micro – particles of gold or tungsten coated with DNA in a method known as biolistics or gene gun.