This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Molecular Biology Techniques, Subject name: Biochemistry
[{'content': 'Northern Blot is used for: \nSelect and explain. \nA. RNA, B. DNA, C. Protein, D. c DNA', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ref: Harpers Illustrated biochemistry, 28th ed, ch. 39,pp-393.Explanation:Northern Blot:Similar to the Southern Blot, but used to probe RNA.Can be used to determine mRNA size, e.g., detect differences in the promoter and terminator sites, etc.Can be used to determine if a particular gene is expressed, and if so, how much, in which tissue type, and when is it expressed in the life cycle', 'role': 'assistant'}]