Restriction endonuclease is best defined as
A) an enzyme which cuts the ends of DNA.
B) an endoribonuclease with precise base specificity.
C) a deoxyribonuclease which cuts double-stranded DNA within a specific sequence.
D) an enzyme which recognizes single-stranded DNA and cuts it at a particular 6 base sequence.

Question

Quizplus · Accepted Answer

Restriction endonuclease is a deoxyribonuclease that recognizes and cleaves double-stranded DNA within specific nucleotide sequences called restriction sites. The specificity of the enzyme is determined by the recognition sequence, which usually consists of 4-8 base pairs. Therefore, option C is the correct definition of restriction endonuclease. Option A is incorrect because it does not specify the specificity of the enzyme. Option B is incorrect because endoribonucleases cleave RNA, not DNA. Option D is incorrect because restriction enzymes do not recognize single-stranded DNA.

Restriction Endonuclease Is Best Defined as