问题 单项选择题

示意图甲、乙、丙、丁为某实验动物感染HIV后的情况,下列说法错误的是()

A.从图甲可以看出,HIV感染过程中存在逆转录现象

B.从图乙可以看出,HIV侵入后机体能产生体液免疫

C.从图丙可以推测,HIV可能对实验药物a敏感

D.从图丁可以看出,HIV对试验药物b敏感

答案

参考答案:D

解析:由图甲可以看出由RNA到DNA的过程,说明有逆转录,故A正确。图乙产生的是抗体,抗体是体液免疫的结果,故B正确。图丙加入药物后T细胞数量增加,说明该药物对HIV可能有抑制作用,故C正确。图丁加入药物b后HIV数量增多,说明该药物对HIV没有抑制作用,故D错误。考点:本题考查HIV相关知识,意在考察考生对知识点的掌握和对图形信息提取分析能力。

单项选择题
阅读理解

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

__1__ From 18-25, according to I.Q. scores;  but you are wiser and more experienced with increasing age.

You are smartest in your 20`s; around 30, your memory begins to go down, particularly your ability to perform mathematical computations, __2__ Your vocabulary at the age of 45, for example , is three times as great as then you graduated form college. At 60, your brain possesses almost four times as much information as it did at the age of21.

__3__ You have the best physical sense of yourself from 15 to 24; the best professional sense form 40 to 49.

Before the age of 24, we believe that our happiest years are yet to come; over 3 0, we believe that they are behind us. A National Health survey agrees: after the age of 30, we “ become more realistic and do not view happiness as a goal in itself. If we maintain our health, achieve professional and emotional goals, happiness, we feel, will follow”.

__4__ Generally between 30 and 39, but the peak(顶峰) varies with different professions.

Mosart wrote a symphony(交响曲) and four sonatas by the age of 8, and Mendelssohn composed(作曲) his best known work A Midsummer Night` s Dream, at 17, but most of the great music was written by men between 33 and 39.

Though the peak in most fields comes early, most Nobel Prize winners did their top research in their late 20`s and 30`---creative people continue to produce work with high quality throughout their lives.__5__.

A.When are you most creative (创造性的)?

B.When are you happiest?

C.When are you smartest?

D.Do you know what I.Q. refers to?E. But your I.Q. for other tasks goes up.

F. Creative people usually produce a lot of works.

G. For the “well-conditioned mind”, there is no upper limit.