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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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After digestion by restriction endonucleases DNA strands can be joined again by which of the following enzymes?
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The correct answer is  DNA is cleaved into fragments by restriction endonucleases. After the fragments of DNA have base paired, the ends are covalently joined by the action of DNA ligase. Restriction enzymes in conjunction with DNA ligase can produce vector containing recombinant or hybrid or chimeric DNA. Ref: Essentials of Biochemistry By Naik, 2012, Page 335.