問題詳情
20. A 400-bp covalently closed circular DNA with a linking number of 35 has 5 negative supercoils. When the linking numberof this DNA is changed to 38 by a topoisomerase, this DNA will have
(A) 3 positive supercoils.
(B) 3 negative supercoils.
(C) 2 positive supercoil.
(D) 2 negative supercoils.
(E) relaxed.
參考答案
答案：D
難度：適中0.473684
統計：A(1),B(4),C(1),D(9),E(0)