构成生命物质的元素约有30种。根据含量,主要有氢、氧、碳和氮,其次是硫和磷,还有钾、钠、钙、氯、镁、铁、铜等,都是生命活动所必需的。它们之间除了共价键以外,还有一些可逆的非共价键相互作用发挥了重要的作用,这些非共价键作用力不包括
A. 氢键
B. 离子键
C. 范德瓦尔力
D. 疏水力
E. 二硫键
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下列除哪个外,均属于参与生物体组成的生物大分子
A. 蛋白质
B. 核酸
C. 多糖
D. 脂肪
E. 甘油
下列碱基中,不出现在RNA中的是
A. T
B. G
C. A
D. C
E. U
Tm值是指
A. 50%的DNA变性时的温度
B. 100%的DNA变性时的温度
C. 相变温度
D. 米氏常数
E. DNA在水中的溶解度
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