学科分类

已选分类 理学生物学遗传学
问答题什么是遗传图上的图距,如何计算?有两个实验室分别用豌豆的两个不同的杂交组合测得的同一染色体上的两个基因之间的图距很不一致。你觉得会出现这种情况吗?造成这种矛盾的原因何在?有可能克服这种矛盾吗?
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问答题何为同源重组,位点特异性重组及跳跃子介导的DNA重组?扼要说明这三种DNA重组方式在机制上的差异。
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问答题F+菌株与Hfr菌株有何异同点?
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问答题在黑腹果蝇中,有一截刚毛(bobbed bristles)基因存在于X和Y的同源区域,所以X和Y上都有这个基因,记作bb,它对野生型基因(+)为隐性。隐性纯合体的刚毛短而细。如有一截刚毛雌蝇(X bb X bb )与纯合体正常刚毛雄蝇(X + Y + )交配,问F 1 和F 2 的基因型和表型的比例如何?
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问答题基因频率、基因型频率
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问答题颠换
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问答题何谓条件型突变?何谓基因间抑制突变?请说明它们在分子遗传学研究中的作用。
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问答题RecA蛋白在同源重组中的作用是什么?
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问答题测交
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问答题简述细胞质遗传的特点。
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问答题终止子(terminator)
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问答题条件致死突变
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问答题简要说明微生物通过哪几种方式进行基因重组?
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问答题杂交稻是利用哪些遗传学理论和技术培育出来的?简述杂交水稻研究和利用的现状。
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问答题简述原核生物和真核生物在染色体结构与DNA复制过程中的主要差异。
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问答题假定有两对基因,每对各有两个等位基因Aa、Bb,以相加效应的方式决定植株的高度,纯合子AABB高50cm,纯合子aabb高30cm,问: 1)这两个纯合子之间杂交,F1高度是多少? 2)在F1×F1杂交后,F2中什么样的基因型表现为40cm高度?
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问答题leucine zipper; zinc finger
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问答题There is a marked difference between the education which every one gets from living with others and the deliberate educating of the young. In the former case the education is incidental; it is natural and important, but it is not the express reason of the association. (46) It may be said that the measure of the worth of any social institution is its effect in enlarging and improving experience, but this effect is not a part of its original motive. Religious associations began, for example, in the desire to secure the favor of overruling powers and to ward off evil influences; family life in the desire to gratify appetites and secure family perpetuity; systematic labor, for the most part, because of enslavement to others, etc. (47) Only gradually was the by-product of the institution noted, and only more gradually still was this effect considered as a directive factor in the conduct of the institution. Even today, in our industrial life, apart from certain values of industriousness and thrift, the intellectual and emotional reaction of the forms of human association under which the world's work is carried on receives little attention as compared with physical output. But in dealing with the young, the fact of association itself as an immediate human fact, gains in importance. (48) While it is easy to ignore in our contact with them the effect of our acts upon their disposition, it is not se easy as in dealing with adults. The need of training is too evident and the pressure to accomplish a change in their attitude and habits is too urgent to leave these consequences wholly out of account. (49) Since our chief business with them is to enable them to share in a common life we cannot help considering whether or not we are forming the powers which will secure this ability. If humanity has made some headway in realizing that the ultimate value of every institution is its distinctively human effect we may well believe that this lesson has been learned largely through dealings with the young. (50) We are thus led to distinguish, within the broad educational process which we have been so far considering, a more formal kind of education—that of direct tuition or schooling. In undeveloped social groups, we find very little formal teaching and training. These groups mainly rely for instilling needed dispositions into the young upon the same sort of association which keeps adults loyal to their group.
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问答题自私DNA(selfish DNA)
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问答题移码突变(frameshift mutation)
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