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Recombinant DNA - Medical Science

Q1:

Bacterial cells protect their own DNA from degradation by restriction endonucleases by

A methylating the DNA at the sites that the enzyme recognizes

B deleting all recognition sites from the genome

C not producing any restriction endonucleases

D having anti restriction endonucleases

ANS:A - methylating the DNA at the sites that the enzyme recognizes

DNA methylation is a process by which methyl groups are added to the DNA molecule. Methylation can change the activity of a DNA segment without changing the sequence. DNA methylation typically acts to repress gene transcription.