问题
单项选择题
DNA双螺旋每旋转一周沿轴上升的高度是（）。
A．0.15nm
B．0.54nm
C．2nm
D．3.4nm
E．3.6nm
答案
参考答案：D
解析：
DNA分子双螺旋一般直径为2nm，螺旋之间螺距为3.4nm。
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DNA双螺旋每旋转一周沿轴上升的高度是（）。
A．0.15nm
B．0.54nm
C．2nm
D．3.4nm
E．3.6nm
参考答案：D
解析：
DNA分子双螺旋一般直径为2nm，螺旋之间螺距为3.4nm。
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