问题 实验题

某研究人员欲探究玉米棒基部、中部、顶部籽粒的发芽率,以便有针对性地进行留种。请分析回答。

(1)若玉米棒顶部、中部的籽粒各用100粒,则玉米棒基部的籽粒要用    粒。

(2)用玉米棒基部、中部、顶部的籽粒进行萌发实验时,应放在        和空气充足的环境中。

(3)若测出玉米棒基部、中部、顶部的籽粒发芽率分别为:93%、91%、80%,请以玉米棒粒部位为横坐标。发芽率为纵坐标画出直方图。

(4)根据实验数据,你认为玉米棒哪一部位的籽粒不宜留作种子?    

答案

(1)100粒 (2)适宜的温度 一定的水分 (3)如下图:

(4)顶部

题目分析:(1)对照实验:在探究某种条件对研究对象的影响时,对研究对象进行的除了该条件不同以外,其他条件都相同的实验.根据变量设置一组对照实验,使实验结果具有说服力.一般来说,对实验变量进行处理的,就是实验组.没有处理是的就是对照组.为了控制变量,因此若玉米棒顶部、中部的籽粒各用100粒,则玉米棒基部的籽粒要用100粒.(2)种子萌发需要的外界环境条件是一定的水分、适宜的温度和充足的空气.因此进行萌发实验时,应将种子放在 一定的水分、适宜的温度和空气充足的环境中.(3)以玉米棒基部、中部、顶部的籽粒发芽率分别为93%、91%、80%,为纵坐标,以种子的部位为横坐标,可以画出直方图如下:

(4)种子的发芽率只有超过90%,才能达到播种要求.否则所测得种子就不能用作播种.玉米棒顶部的籽粒的发芽率是80%.因此玉米棒顶部的籽粒不宜留作种子.

故答案为:(1)100;(2)一定的水分;适宜的温度;(3)如下图:(4)顶部.

单项选择题
单项选择题

Questions 6-10 are based on the following passage.
The term control is highly—and unjustifiably—unpopular. Some of its unpopularity can be traced to educational and philosophical writings that have addressed issues of freedom, self- determination, self-worth, individuality, and other humanistic concerns—concerns often equated with liberal and permissive child-rearing and educational methods. They are the concerns that define the spirit of these times. No teacher wants to be nonliberal and restrictive. And there is little doubt that the deliberate exercise of control is restrictive. Is control therefore unethical
There is, of course, no simple answer, ff there were, there would be little controversy, and behaviorists and humanists would have much less to disagree about.
Consider, first, that control is not only inevitable but also necessary. There is no doubt that teachers, by virtue of their position and by virtue of their duties, have control. Indeed, it is not at all unreasonable to insist that the exercise of control is one of the teacher’s most important duties. We are not speaking here of a fear-enforced control that might have been characteristic of some of yesterday’s schools. Control can be achieved, or at least facilitated, in a variety of gentle ways, some of which can be learned.
Parents too control their children (or at least try), often by setting limits for their behavior. Part of the successful socialization process requires that children be prevented from engaging in behaviors that might be injurious to themselves or to others. Thus, parents do not permit their children to play with the dinner as it is cooking on the stove, to insert knives into electrical outlets, to jump off ladders, or to swim in dangerous waters. Less extreme instances of control involve the teaching of socially appropriate behavior, of values and morals—of "shoulds" and "should nots". It is less by accident than by virtue of parental control that children learn not to deface wall, steal other people’s property, or kill the neighbor’s god. In short, certain standards of behavior are learned at least partly as a function of parental control. Whether that control involves reinforcement, punishment, models, reasoning, or a combination of these and other strategies, we cannot avoid the fact that control is being exercised.
The classroom situation is not really very different. Teachers have often been described as acting [in loco parentis]—in the place of parents. More precisely, teachers have been urged to act in all ways as might a wise, judicious, and loving parent. And there is, in fact, no great incompatibility between values held in highest esteem by those who describe themselves as humanistically oriented and the techniques of behavior control that have been described by science. Love, empathy, warmth, genuineness, and honesty can go a long way toward ensuring a classroom climate corducive to and learning and development. In spite of these highly desirable qualities, however, discipline problems are not uncommon in classrooms. That teachers should judiciously administer rewards and punishment in an effort to maintain an effective educational environment does not mean that they care less for their students; indeed, in might well indicate that they care more.

Which of the following can be an appropriate title for the passage

A.Control or Liberty

B.Teacher’s Control or Parent’s Restriction

C.The Ethics of Control

D.How to Use Control Scientifically