1．肾脏的功能单位为： Ａ．肾单位 Ｂ．肾小球 Ｃ．肾皮髓质 Ｄ．肾小囊 Ｅ．肾小球旁器 2．正常情况下，肾小球滤过液（原尿）在肾小管中被吸收的占总量 Ａ．10％ Ｂ．30％ Ｃ．50％ Ｄ．80％ Ｅ．99％

14.1 Introduction 14.2 Breakage and reunion involves heteroduplex DNA 14.3 Double-strand breaks initiate recombination 14.4 Double-strand breaks initiate snapsis 14.5 Bacterial recombination involves single-strand assimilation 14.6 Gene conversion accounts for interallelic recombination 14.7 Topological manipulation of DNA 14.8 Specialized recombination involves breakage and reunion at specific sites 14.9 Repair systems correct damage to DNA 14.10 Excision repair systems in E. coli 14.11 Controlling the direction of mismatch repair 14.12 Retrieval systems in E. coli 14.13 RecA triggers the SOS system 14.14 Eukaryotic repair systems

对二维rv.除每个rv各自的概率特 性外,相互之间可能还有某种联系 怎样用一个数去反映这种联系? 数E(-(X)[-E(Y) 便反映了r.v.X,Y之间的某种关系

1.按定积分定义证明:kdx=k(b-a) 2.通过对积分区间等分分割,并取适当的点集{},把定积分看作是对应的积分和的极限, 来计算下列定积分: (2)e'dx; (3)e*dx (4)(a