已选分类
理学生物学
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。
问答题RecA蛋白在同源重组中的作用是什么?
问答题测交
问答题简述细胞质遗传的特点。
问答题终止子(terminator)
问答题条件致死突变
问答题简要说明微生物通过哪几种方式进行基因重组?
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。
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。
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?
问答题leucine zipper; zinc finger
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.
问答题自私DNA(selfish DNA)
问答题移码突变(frameshift mutation)
问答题原噬菌体
问答题为什么DNA双螺旋中维持特定的沟很重要?
问答题要识别刚孵出的小鸡的性别是很困难的,但是很容易区别它们的羽毛是芦花的还是非芦花的。设:
问答题IS元件整合到靶位点时会发生什么?
问答题上位效应
问答题intron; exon
