<prompt> What do restriction endonucleases do?Cut ds DNA at specific sitesCut RNA at specific sitesCut ss DNA at specific sitesBreak peptide chains  <response>: Restiction Endonucleases RE : In order to transfer a gene, it is to be first selectively split from the parent DNA. It is usually achieved by the restriction endonucleases. RE have specific recognition sites where they cut the DNA. There are 800 such enzymes now available commercially. These enzyms recognize specific sequence with palindrome arrangement. REF :DM VASUDEVAN textbook; 8th EDITION; Page no :601 