THE MOLECULAR BASIS OF INHERITANCE
RECOMBINANT DNA
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Which of the following are TRUE of restriction enzymes? I. It restricts transcriptionI. II. It is found in all eukaryotic cells. III. It acts on palindromic sequences. IV. It is sensitive to changes in temperature and pH.
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I and II
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I and III
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II and IV
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III and IV
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Explanation:
Detailed explanation-1: -Answer and Explanation: Restriction enzymes do not cut at regular intervals; instead, they cut the DNA anywhere they find their specific restriction site.
Detailed explanation-2: -No, eukaryotic cells do not have restriction endonucleases. This is because the DNA of eukaryotes is highly methylated by a modification enzyme, called methylase. Methylation protects the DNA from the activity of restriction enzymes.
Detailed explanation-3: -Where do restriction enzymes come from? Restriction enzymes are found in bacteria. Bacteria use restriction enzymes to kill viruses – the enzymes attack the viral DNA and break it into useless fragments.
There is 1 question to complete.