16. Which of the following statements about type II restriction enzymes is(are) false?
1. They are sequence-specific DNA endonucleases.
2. Many make staggered (off-center) cuts within their recognition sequences. Some cut DNA to generate blunt ends.
3. They cut both DNA strands at the same base pair.
4. They are part of a bacterial defense system in which foreign DNA is cleaved.
5. The size of the DNA region specifically recognized by type II restriction enzymes is typically 8 to 12 base pairs.
(A) 1 and 3 are false.
(B) 2 and 4 are false.
(C) 3 and 5 are false.
(D) Only 4 is false.
(E) Only 5 is false.
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統計: 尚無統計資料
統計: 尚無統計資料