Chapter 20

Last update by mayur on 03/27/2014
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How does a bacterial cell protect its own DNA from restriction enzymes?

A) adding methyl groups to adenines and cytosines

B) using DNA ligase to seal the bacterial DNA into a closed circle

C) adding histones to protect the double-stranded DNA

D) forming "sticky ends" of bacterial DNA to prevent the enzyme from attaching

E) reinforcing the bacterial DNA structure with covalent phosphodiester bonds

Answer:

A) adding methyl groups to adenines and cytosines

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