问题 探究题

某校生物科技活动小组建立了一个小型的农业生态园,在园内,同学们开展了一系列植物栽培和科学探究活动,请分析回答下列问题:

(1)在移栽植物幼苗时,为了提高成活率,往往选择在阴雨天或者傍晚移栽,这样做的目的是为了                                                  

(2)为了探究提高生态园内蔬菜产量的科学方法,同学们选择萝卜作为研究对象进行实验.他们在四个温室中分别种植了相同的萝卜种子,温室内的温度、二氧化碳浓度和土壤液控制情况如下图所示(每个温室的光照等其他条件相同):

温室ABCD
二氧化碳浓度0.03%0.1%0.1%0.1%
温度20℃20℃30℃30℃
培养液土壤浸出液土壤浸出液土壤浸出液蒸馏水
①他们应该选用什么样的种子进行实验?                        

②温室B中的萝卜幼苗比温室A中的萝卜幼苗长得快,其原因是                         

③栽培一段时间后,长势最差的温室是                      

④同学们收获的萝卜,由于存放时间较长,出现了“空心”现象,这是因为                     

⑤为探究温度对萝卜幼苗光合作用强度的影响,应该选择______两组进行对照实验;若探究二氧化碳浓度对萝卜幼苗光合作用强度的影响,能否选用A、C两组进行对照实验?                  ,理由是                                    

答案

(1)降低蒸腾作用的强度  (2)①胚是完整的,粒大饱满的  ②温室B内二氧化碳的浓度高   ③D   ④呼吸作用分解了有机物   ⑤B C    不能,有两个变量,温度和二氧化碳的浓度,这样结果不准确

题目分析:(1)植物体内的水分以气体的形式散发到大气中的过程叫蒸腾作用,叶是蒸腾作用的主要器官,影响蒸腾作用的因素是光照强度、空气的流通状况、大气湿度和温度等,在阴天或傍晚移栽植物,并剪去大量枝叶,都可降低植物的蒸腾作用,提高移栽的成活率。

(2)①种子的萌发的外界条件为适量的水分、适宜的温度和充足的空气,自身条件是有完整而有活力的胚及胚发育所需的营养物质,而尽量选用粒大饱满的种子,这样的种子中含有较多的营养物质,可使种子萌发时有充足的营养,萌发出的幼苗更茁壮;

②二氧化碳是光合作用的原料,温室B与温室A相比较,温室B内的二氧化碳的浓度高,为光合作用提供了足够的原料,导致光合作用制造的有机物多,因此温室B中的萝卜幼苗比温室A中的萝卜幼苗长得快;

③植物的生长需要水和无机盐,所以栽培一段时间后,长势最差的温室是没有无机盐的D温室;

④呼吸作用的公式:有机物+氧→二氧化碳+水+能量,呼吸作用是生物的共同特征,每时每刻都在进行,由于萝卜在贮存时能进行呼吸作用,而呼吸作用是把体内储存的有机物加以分解产生二氧化碳和水,所以萝卜由于呼吸作用消耗了体内的大量有机物而使有机物减少,因此会出现空心的现象;

⑤要探究温度对萝卜幼苗光合作用强度的影响,就要以温度为变量设置对照实验,因此他们应选择表中的B、C两组进行对照实验;探究二氧化碳浓度对萝卜幼苗光合作用强度的影响,就要以二氧化碳的浓度为变量设置对照实验,A、C两组实验中存在两个变量,不能确定实验结果是由哪个因素引起的,因此A、C两组不能作为一组对照实验,应用表中的A、B两组作为对照实验来探究氧化碳浓度对萝卜幼苗光合作用强度的影响。

解答题
单项选择题

Ask any employee at an level in any company what they dislike about their job and somewhere on the list you will find a complaint about the system of performance appraisals. It does seem strange that an idea which was supposed to benefit both individuals and the company should be so universally disliked, but the staff appraisal is now one of the biggest causes of dissatisfaction at work. In the United States there have even been cases of unhappy workers taking their employers to court over appraisal interviews. It is in a company’s interest to combat this situation, but, before reversing the appraisal’s negative associations, an organization needs to pinpoint the underlying reasons which have contributed to them.

Problems with appraisals can fall into two main areas--those arising from the scheme itself and those arising from the implementation and understanding of that scheme. Naturally it is easier to tackle those in the former category; indeed, some companies have developed schemes following legal guidelines. These guidelines suggest that a successful scheme should have a clear appeal process, that any negative feedback should be accompanied by "evidence" such as dates, times and outcomes and that, most importantly, ratings should reflect specific measurable elements of the job requirements.

It is not always necessary to resort to legal advice however. Some changes to current schemes are simply a matter of logic. For instance, if employees are constantly encouraged to work in teams and to assume joint responsibility for their successes and failures, it makes little sense for the appraisals to focus on individuals, as this may lead to resentments and create divisions within the group. It is possible, and in some cases more suitable, to arrange appraisals where performance is rated for the group.

Staff also need to be educated about the best way to approach appraisals. Managers often find that they are uncomfortable being asked to take on a more supportive role than they are used to without having had any training. Those being appraised may see it as a chance to air their grievances and highlight the company’s failings rather than consider their own role. Both parties view the process as a necessary evil, to be gone through once or twice a year, and then forgotten about. The importance given to the appraisal stems from the fact that, despite all the talk of the interview being a chance for management and employees to come together and exchange ideas, set joint targets and improve the way decisions are reached, the reality is that they are often nothing more than the pretext on which pay rises are given, or not given. Pay is, of course, a subject that always leads to problems.

Given the problems associated with staff appraisals, why is it that, with no legal requirement, companies continue to run them The answer is simple, it is impossible to manage something you know nothing about. As any Human Resources manager can tell you, the best way to learn about someone is to talk to them. Effective people management relies on knowledge and appraisals are still the best way to build up that bank of knowledge.

Individual appraisals are not always very effective because().

A.teams much prefer to be awarded a group rating

B.everybody works in teams these days

C.team members share liability for results

D.team leaders sense resentment between members