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用体外实验的方法可合成多肽链．已知苯丙氨酸的密码子是UUU，若要在体外合成同位素标记的多肽链，所需的材料组合是（ ） ①同位素标记的tRNA ②蛋白质合成所需的酶 ③同位素标记的苯丙氨酸 ...
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高三下学期生物《》真题及答案
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下列为某多肽链和控制它合成的一段DNA链甲硫氨酸的密码子是AUG甲硫氨酸一脯氡酸一苏氨酸一甘氨酸一缬
这段多肽链中有4个“一CO—HN一”的结构
决定这段多肽链的遗传密码子依次是AUG、CC
ACC.GGG、GUAC.这段DNA中的①链起了转录模板的作用
若发生基因突变，则该多肽链的结构一定发生改变
科学家已经证明密码子是mRNA上决定一个氨基酸的三个相邻的碱基1根据理论推测mRNA上的三个相邻的碱
已知有三种氨基酸的密码子是甲硫氨酸AUG色氨酸UGG苯丙氨酸UUU或UUC某多肽链的一段氨基酸序列—
图表示某DNA片段遗传信息的传递过程①～⑤表示物质或结构abc表示生理过程请据图回答下列问题可能用到
下图表示基因控制蛋白质合成的过程请分析回答1基因是有遗传效应的___________片段2过程Ⅰ称为
科学家已经证明密码子是mRNA上决定一个氨基酸的三个相邻的碱基1根据理论推测mRNA上的三个相邻的碱
下图表示某DNA片段遗传信息的传递过程①～⑤表示物质或结构abc表示生理过程请据图回答下列问题可能用
下列为某多肽链和控制它合成的一段DNA链甲硫氨酸的密码子是AUG甲硫氨酸—脯氨酸—苏氨酸—甘氨酸—缬
这段多肽链中有4个“—CO—HN—”的结构
决定这段多肽链的遗传密码子依次是AUG、CC
ACC.GGG、GUAC.这段DNA中的①链起了转录模板的作用
若发生基因突变，则该多肽链的结构一定发生改变
如图表示某DNA片段遗传信息的传递过程①～⑤表示物质或结构abc表示生理过程请据图回答下列问题可能用
密码子的阅读方向是____多肽链合成的方向是____
mRNA上决定一个氨基酸的三个相邻的碱基叫密码子根据理论推测mRNA上三个相邻的碱基可以构成____
甲硫氨酸的密码子AUG通常被称为起始密码子即翻译过程从该密码子开始能够得出这一结论的事实是
信使RNA最前端的3个碱基通常都是AUG
甲硫氨酸只有一个密码子，其它氨基酸有多个密码子
所有生物中都含有甲硫氨酸的密码子
新合成多肽链的第一个氨基酸通常是甲硫氨酸
用体外实验的方法可合成多肽链．已知苯丙氨酸的密码子是UUU若要在体外合成同位素标记的多肽链所需的材
①②④
②③④
③④⑤
①③⑤
长期以来科学家们对遗传的物质基础进行了大量的研究并得出了一些科学结论第一个被科学家破译的是决定苯丙氨
44.下图表示控制某多肽链合成的一段DNA链已知甲硫氨酸的密码子是AUG合成的多肽链的氨基酸组成为甲
该多肽链中有4个“—CO—HN—”结构
决定该多肽链的遗传密码子依次是AUG、CC
ACC.GGG、GUA C.上图DNA片段中的①链起了转录模板的作用
若发生基因突变，则该多肽链的结构一定发生改变
关于遗传密码正确的是
多数氨基酸都有一种以上的密码子
一种密码子只代表一种氨基酸
鸟氨酸、瓜氨酸和羟脯氨酸都有遗传密码子
起始部位的 AUG同时是起始密码子和蛋氨酸密码子
终止密码子使多肽链合成终止
在大肠杆菌的蛋白质合成系统中合成一条多肽链如下fMet-Arg-His-Ala-Val已知Met的t
下图表示控制某多肽链合成的一段DNA链已知甲硫氨酸的密码子是AUG合成的多肽链的氨基酸组成为甲硫氨酸
该多肽链中有4个“―CO―HN―”结构
决定该多肽链的遗传密码子依次是AUG、CC
ACC.GGG、GUAC.上图DNA片段中的①链起了转录模板的作用
若发生基因突变，则该多肽链的结构一定发生改变
下图表示控制某多肽链合成的一段DNA链已知甲硫氨酸的密码子是AUG合成的多肽链的氨基酸组成为甲硫氨酸
该多肽链中有4个“—CO—HN—”结构
决定该多肽链的遗传密码子依次是AUG、CC
ACC.G.GG、GUAC.上图DNA片段中的①链起了转录模板的作用
若发生基因突变，则该多肽链的结构一定发生改变
请回答下列有关真核细胞中遗传信息及其表达的问题1已知某基因片段碱基排列如下图由它控制合成的多肽中含有
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