This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
[{'content': 'DNA fragments formed by the action of Restriction Endonucleases, are separated by: \nSelect and explain. \nA. Gel electrophoresis, B. Agarose gel eletrophoresis, C. Paper Chromatography, D. High pressure liquid chromatography', 'role': 'user'}, {'content': "Answer: B \nExplanation: B i.e. Agarose gel electrophoresis - Restriction endonuclease (restriction enzyme) makes 2 incisions through sugar phosphate backbone (phospho diester bond) of each strand of ds DNAQ at specific sequence k/a recognition sequences or restriction site. So RE restricts viral (bacteriophage - DNA) replicationQ and protects bacteria (prokaryote) from infection by virusQ. - RE cuts both strands of double stranded (ds) DNA at specific restriction sites with palindromic (inverse repeat) arrangement; thus producing smaller, manageable fragments with sho sequenes and sticky/ blunt endsQ. These restriction fragments can be isolated by agarose gel /polyacrylamide - electrophoresisQ or HPLC. After digestion by restriction endonucleases the DNA ends can be ligated (joined/ annealed) by ' DNA-ligaseQ", 'role': 'assistant'}]