試題詳解

80. Which statement for DNA supercoiling is FALSE?
(A) In prokaryotes, class I topoisomerases cut the phosphodiester backbone of one strand of DNA, pass the other end through, and then reseal the backbone.
(B) Class II topoisomerases cut both strands of DNA, pass some of the remaining DNA helix between the cut ends, and then reseal.
(C) DNA helicase is a bacterial topoisomerase that introduces negative supercoils into DNA.
(D) In eukaryotes, DNA forms a complex called chromatin that mainly contains histones.
(E) A relaxed DNA can be converted either to positive supercoil or negative supercoil.