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Question
Do eukaryotic cells have restriction endonucleases? Justify your answer.
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Solution
Yes, restriction endonucleases are found in eukaryotic cells. Restriction endonuclease acts by examining the length of the DNA sequence. When it finds its specific recognition sequence, it binds to the DNA and cuts both strands of the double helix at specific points in the sugar-phosphate backbones. Each restriction endonuclease recognises specific palindromic nucleotide sequences in DNA.
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\[\ce{5' C - T - G - C - A \overset{\downarrow}{-}{G 3'}}\]
\[\ce{3' G\underset{\uparrow}{-} A - C - G - T - C 5'}\]
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