现场只在受害人指甲中找到案犯的一些皮肤组织【-】课件

现场只在受害人指甲中找到案犯的一些皮肤组织【-】课件1现场只在受害人指甲中找到案犯的一些皮肤组织，如何破案？请你破案现场只在受害人指甲中找到案犯的一些皮肤组织，如何破案2一、DNA的基本单位——脱氧核糖核苷酸②③

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腺嘌呤脱氧核糖核苷酸鸟嘌呤脱氧核糖核苷酸胸腺嘧啶脱氧核糖核苷酸胞嘧啶脱氧核糖核苷酸脱氧核糖含氮碱基磷酸一、DNA的基本单位——脱氧核糖核苷酸②③①腺嘌呤脱氧核3核糖核苷酸脱氧核糖核苷酸脱氧核糖核糖尿嘧啶核糖核苷酸脱氧核糖核苷酸脱氧核糖核糖尿嘧啶4脱氧核苷酸的结构与种类脱氧核苷酸脱氧核苷磷酸脱氧核糖含氮碱基嘌呤嘧啶腺嘌呤（A）鸟嘌呤（G）胞嘧啶（C）胸腺嘧啶（T）脱氧核苷酸种类腺嘌呤脱氧核苷酸鸟嘌呤脱氧核苷酸胞嘧啶脱氧核苷酸胸腺嘧啶脱氧核苷酸脱氧核苷酸的结构与种类脱氧核苷酸脱氧核苷磷酸脱氧核糖含氮碱基5DNA的组成元素脱氧核苷酸规则的双螺旋结构1DNA的结构DNA的基本单位DNA的多样性DNA的特异性碱基对的排列顺序千变万化特定的碱基排列顺序DNA的空间结构C、H、O、N、PDNA的组成元素脱氧核苷酸规则的双螺旋结构1DNA的结6DNA的分子结构《自然》杂志上发表的论文沃森克里克(美国生物学家)(英国物理学家)DNA的分子结构《自然》杂志上发表的论文沃森7DNA的空间结构--规则的双螺旋结构1953年由沃森和克里克提出1.DNA分子是由两条反向平行的脱氧核苷酸长链盘旋而成的规则双螺旋结构2.脱氧核糖与磷酸交替连结，排列在外侧，构成基本骨架；碱基排列在链的内侧。3.两条链上的碱基通过氢键连结起来，形成碱基对。碱基对的组成有特定的规律：即腺嘌呤一定与胸腺嘧啶配对，鸟嘌呤一定同胞嘧啶配对。DNA的空间结构--规则的双螺旋结构1953年由沃森和克里克8DNA分子的结构特点DNA分子的结构特点9DNA分子的特性多样性特异性稳定性DNA作为遗传物质的理论证据DNA分子的特性多样性特异性稳定性DNA作为遗传物质的理论证10利用碱基互补配对规律的计算规律一：DNA双链中的两条互补链的碱基相等，任意两个不互补的碱基之和恒等，占碱基总数的50%。即：A+G＝T+C＝A+C＝T+G＝50%，（A+G）/(T+C)＝(A+C)/(G+T)＝(T+C)/(A+G)＝1。规律二：在DNA双链中的一条单链的A+GT+C的值与另一条互补链的T+CA+G的值互为倒数关系。规律三：DNA双链中，一条单链的A+TG+C的值与另一条互补链的A+TG+C的值是相等的，也与整个DNA分子中的A+TG+C的值相等。利用碱基互补配对规律的计算规律一：DNA双链中的两条互补链的11巩固提高1.已知一段双链DNA有100个碱基对，其中腺嘌呤有60个,请问鸟嘌呤的比例是_________，(A+C):(T+C)的值是__________。A+T+C+G=200A=TC=G100401=1A+G=G=40A+CT+G巩固提高1.已知一段双链DNA有100个碱基对，其中腺嘌呤12ATCGTAGCnm巩固提高A+ＧT+Ｃ=am链：=an链：T+CA+G=1/aA+ＧT+Ｃn链：整个DNA：A+ＧT+Ｃ=1A+TG+Ｃ=bm链：n链：=bT+AC+G=bA+TG+Ｃn链：整个DNA：A+TG+Ｃ=b2.ATCGT13【例1】(2000年广东高考题)已知一段双链DNA中碱基的对数和腺嘌呤的个数，能否知道这段DNA中4种碱基的比例和(A+C)：(T+G)的值()A能B否C只能知道(A+C)：(T+G)的值D只能知道四种碱基的比例

AATGC

TACG已知腺嘌呤A的个数，等于已知T的数目(A＝T)。知道DNA中碱基对数，可以求出C+G的数目，也就可以求出G和C的数目(G＝C)。在双链DNA中，A+CT+G＝1。

【例1】(2000年广东高考题)AA14【例2】(1998年上海高考题)在含有4种碱基的DNA区段中，有腺嘌呤a个，占该区段全部碱基的比例为b，则()Ab≤05Bb≥05C胞嘧啶为a（12b-1)个D胞嘧啶为b(12a-1)个C【解析】根据碱基互补配对原则，有A＝T，C＝G，ATC

TAGC，A＝a＝T，AA+T+C+G＝ba2a+G+C＝bG+C＝ab-2a，故G＝C＝12(ab-2a)＝a(12b-1)【例2】(1998年上海高考题)C【解析】根据碱基互15敬请专家指正谢谢同学合作敬请专家指正168oEU0gwM$8oDT+fvL!7nDT+euK#6mCS-euK#5lBR)dtJZ5lBQ(csIY4kAQ(csHX3jzP*brHX3iyO&aqGW2iyO&9pFV1hxN%9pFU0gwM$8oEU0gwL!7nDT+fvL!7mCS-euK#6mCS)dtJZ5lBR)dtJY4kAQ(csIY4kzP*brHX3jzP*bqGW2iyO&aqGW1hxN%9pFV1hxN$8oEU0gwM$8oDT+fvL!7nDT+fuK#6mCS-euK#5lBR)dtJZ5lBR(csIY4kAQ(csHX3jzP*brHX3jyO&aqGW2iyO&9pFV1hxN%9pFU0gwM$8oEU0gwL!7nDT+fvL!7mCS-euK#6mCS-dtJZ5lBR)dtJY4kAQ(csIY4kAP*brHX3jzP*bqGW2iyO&aqGW2hxN%9pFV1hxN$8oEU0gwM$8oET+fvL!7nDT+fuK#6mCS-euK#6lBR)dtJZ5lBR(csIY4kAQ(csHX3jzP*brHX3jyO&aqGW2iyO&9pFV1hxN%9pFV0gwM$8oEU0gwL!7nDT+fvL!7nCS-euK#6mCS-dtJZ5lBR)dtJZ4kAQ(csIY4kAP*brHX3jzP*brGW2iyO&aqGW2hxN%9pFV1hxN%8oEU0gwM$8oET+fvL!7nDT+fuK#6mCS-euK#6lBR)dtJZ5lBR(csIY4kAQ(csIX3jzP*brHX3jyO&aqGW2iyO&apFV1hxN%9pFV0gwM$8oEU0gwM!7nDT+fvL!7nCS-euK#6mCS-etJZ5lBR)dtJZ4kAQ(csIY4kAQ*brHX3jzP*brGW2iyO&aqGW2hxN%9pFV1hxN%8oEU0gwM$8oET+fvL!7nDT+fvK#6mCS-euK#6lBR)dtJZ5lBR)csIY4kAQ(csIX3jzP*brHX3jzO&aqGW2iyO&apFV1hxN%9pFV1gwM$8oEU0gwM!7nDT+fvL!7nDS-euK#6mCS-etJZ5lBR)dtJZ4kAQ(csIY4kAQ*brHX3jzP*brGW2iyO&aqGW2ixN%9pFV1hxN%8oEU0gwM$8oEU+fvL!7nDT+fvK#6mCS-euK#6mBR)dtJZ5lBR)csIY4kAQ(csIY3jzP*brHX3jzO&aqGW2iyO&aqFV1hxN%9pFV1gwM$8oEU0gwM!7nDT+fvL!7nDS-euK#6mCS-etJZ5lBR)dtJZ5kAQ(csIY4kAQ*brHX3jzP*brHW2iyO&aqGW2ixN%9pFV1hxN%9oEU0gwM$8oEU+fvL!7nDT+fvL#6mCS-euK#6mBR)dtJZ5lBR)dsIY4kAQ(csIY3jzP*brHX3jzP&aqGW2iyO&aqFV1hxN%9pFV1gwM$8oEU0gwM$7nDT+fvL!7nDS-euK#6mCS-euJZ5lBR)dtJZ5kAQ(csIY4kAQ(brHX3jzP*brHW2iyO&aqGW2iyN%9pFV1hxN%9oEU0gwM$8oEU0fvL!7nDT+fvL#6mCS-euK#6mCR)dtJZ5lBR)dsFV1hxN%9pEU0gwM$8oEU0fvL!7nDT+fvL!6mCS-euK#6mCR)dtJZ5lBR)dtIY4kAQ(csIY4jzP*brHX3jzP*aqGW2iyO&aqGV1hxN%9pFV1hwM$8oEU0gwM$8nDT+fvL!7nDT-euK#6mCS-euKZ5lBR)dtJZ5lAQ(csIY4kAQ(crHX3jzP*brHX2iyO&aqGW2iyO%9pFV1hxN%9pEU0gwM$8oEU0gvL!7nDT+fvL!6mCS-euK#6mCS)dtJZ5lBR)dtIY4kAQ(csIY4jzP*brHX3jzP*aqGW2iyO&aqGV1hxN%9pFV1hxM$8oEU0gwM$8nDT+fvL!7nDT+euK#6mCS-euKZ5lBR)dtJZ5lBQ(csIY4kAQ(crHX3jzP*brHX3iyO&aqGW2iyO%9pFV1hxN%9pFU0gwM$8oEU0gvL!7nDT+fvL!6mCS-euK#6mCS)dtJZ5lBR)dtIY4kAQ(csIY4kzP*brHX3jzP*aqGW2iyO&aqGW1hxN%9pFV1hxM$8oEU0gwM$8oDT+fvL!7nDT+euK#6mCS-euK#5lBR)dtJZ5lBQ(csIY4kAQ(csHX3jzP*brHX3iyO&aqGW2iyO%9pFV1hxN%9pFU0gwM$8oEU0gvL!7nDT+fvL!7mCS-euK#6mCS)dtJZ5lBR)dtJY4kAQ(csIY4kzP*brHX3jzP*bqGW2iyO&aqGW1hxN%9pFV1hxN$8oEU0gwM$8oDT+fvL!7nDT+fuK#6mCS-euK#5lBR)dtJZ5lBQ(csIY4kAQ(csHX3jzP*brHX3iyO&aqGW2iyO&9pFV1hxN%9pFU0gwM$8oEU0gwL!7nDT+fvL!7mCS-euK#6mCS&aqGW2iyO&9pFV1hxN%9pFV0gwM$8oEU0gwL!7nDT+fvL!7nCS-euK#6mCS-dtJZ5lBR)dtJZ4kAQ(csIY4kAP*brHX3jzP*brGW2iyO&aqGW2hxN%9pFV1hxN%8oEU0gwM$8oET+fvL!7nDT+fvK#6mCS-euK#6lBR)dtJZ5lBR)csIY4kAQ(csIX3jzP*brHX3jyO&aqGW2iyO&apFV1hxN%9pFV0gwM$8oEU0gwM!7nDT+fvL!7nCS-euK#6mCS-etJZ5lBR)dtJZ4kAQ(csIY4kAQ*brHX3jzP*brGW2iyO&aqGW2ixN%9pFV1hxN%8oEU0gwM$8oEU+fvL!7nDT+fvK#6mCS-euK#6lBR)dtJZ5lBR)csIY4kAQ(csIX3jzP*brHX3jzO&aqGW2iyO&apFV1hxN%9pFV1gwM$8oEU0gwM!7nDT+fvL!7nDS-euK#6mCS-etJZ5lBR)dtJZ5kAQ(csIY4kAQ*brHX3jzP*brHW2iyO&aqGW2ixN%9pFV1hxN%8oEU0gwM$8oEU+fvL!7nDT+fvK#6mCS-euK#6mBR)dtJZ5lBR)csIY4kAQ(csIY3jzP*brHX3jzO&aqGW2iyO&aqFV1hxN%9pFV1gwM$8oEU0gwM$7nDT+fvL!7nDS-euK#6mCS-euJZ5lBR)dtJZ5kAQ(csIY4kAQ*brHX3jzP*brHW2iyO&aqGW2ixN%9pFV1hxN%9oEU0gwM$8oEU+csIY4kAQ(brHX3jzP*brHX2iyO&aqGW2iyN%9pFV1hxN%9oEU0gwM$8oEU0fvL!7nDT+fvL#6mCS-euK#6mCR)dtJZ5lBR)dsIY4kAQ(csIY4jzP*brHX3jzP&aqGW2iyO&aqGV1hxN%9pFV1hwM$8oEU0gwM$8nDT+fvL!7nDT-euK#6mCS-euKZ5lBR)dtJZ5lAQ(csIY4kAQ(brHX3jzP*brHX2iyO&aqGW2iyN%9pFV1hxN%9pEU0gwM$8oEU0fvL!7nDT+fvL!6mCS-euK#6mCR)dtJZ5lBR)dtIY4kAQ(csIY4jzP*brHX3jzP*aqGW2iyO&aqGV1hxN%9pFV1hxM$8oEU0gwM$8nDT+fvL!7nDT-euK#6mCS-euKZ5lBR)dtJZ5lAQ(csIY4kAQ(crHX3jzP*brHX2iyO&aqGW2iyO%9pFV1hxN%9pEU0gwM$8oEU0gvL!7nDT+fvL!6mCS-euK#6mCS)dtJZ5lBR)dtIY4kAQ(csIY4kzP*brHX3jzP*aqGW2iyO&aqGV1hxN%9pFV1hxM$8oEU0gwM$8nDT+fvL!7nDT+euK#6mCS-euKZ5lBR)dtJZ5lBQ(csIY4kAQ(crHX3jzP*brHX3iyL!7nDT+fuK#6mCS-euK#5lBR)dtJZ5lBQ(csIY4kAQ(csHX3jzP*brHX3iyO&aqGW2iyO&9pFV1hxN%9pFU0gwM$8oEU0gwL!7nDT+fvL!7mCS-euK#6mCS-dtJZ5lBR)dtJY4kAQ(csIY4kAP*brHX3jzP*bqGW2iyO&aqGW2hxN%9pFV1hxN$8oEU0gwM$8oDT+fvL!7nDT+fuK#6mCS-euK#5lBR)dtJZ5lBR(csIY4kAQ(csHX3jzP*brHX3jyO&aqGW2iyO&9pFV1hxN%9pFV0gwM$8oEU0gwL!7nDT+fvL!7nCS-euK#6mCS-dtJZ5lBR)dtJZ4kAQ(csIY4kAP*brHX3jzP*bqGW2iyO&aqGW2hxN%9pFV1hxN$8oEU0gwM$8oET+fvL!7nDT+fuK#6mCS-euK#6lBR)dtJZ5lBR(csIY4kAQ(csIX3jzP*brHX3jyO&aqGW2iyO&apFV1hxN%9pFV0gwM$8oEU0gwM!7nDT+fvL!7nCS-euK#6mCS-dtJZ5lBR)dtJZ4kAQ(csIY4kAP*brHX3jzP*brGW2iyO&aqGW2hxN%9pFV1hxN%8oEU0gwM$8oET+fvL!7nDQ*brHX3jzP*brGW2iyO&aqGW2ixN%9pFV1hxN%8oEU0gwM$8oEU+fvL!7nDT+fv