掌状脉

通过胰岛素样生长因子促蛋白质合成的激素是（）

A.甲状腺激素

B.肾上腺皮质激素

C.抗利尿激素

D.生长激素

       狗，学名“犬”。一种常见的犬科哺乳动物。通常被称为“人类最忠实的朋友”。

       狗起源于狼，是人类最早驯化的家畜之一。狗形状大小不一，颜色和品种都很多，而且通人性，是一种惹人喜爱的动物，也是一种对人类帮助最大的动物。

       狗生性灵活，聪明怜俐。狗的智力是高等动物——人类的智力的四分之一。而且狗的嗅觉比我们人类灵敏1000倍；狗特别警觉，连睡觉时都会将耳朵贴近地面或墙壁，只要一有动静便会马上进入“警戒状态”。通过人工训练的狗，成为人类很重要的帮手，普遍用于看家护院、捕猎畜牧（猎狗、牧羊犬）、侦察监测（军犬、警犬、海关缉毒犬、机场火药监测犬）、搜查救助（搜救犬）、照顾生活（导盲犬）……狗甚至还参加过太空实验，在上世纪五六十年代，苏联太空署使用一群狗进行次轨道和轨道上的太空飞行，以确认人类太空飞行的可行性。可以说，没有哪一种动物像狗一样在以这么多的方式为我们服务。

       狗通人性，这一点特别有趣。狗有虚荣心，喜欢人们称赞表扬它。当它办一件好事，或做一些小技巧活动，你拍手赞美它，抚摸它，它就会像吃了一顿丰盛美餐那样心满意足。狗也有害羞心，如它做错了事，挨了主人的骂，它就会躲在什么地方，等肚子饿了才出来。狗除了用叫声表达感情，还用尾巴来“说话”。一般在兴奋或见到主人高兴时，就会摇头摆尾，尾巴不仅左右摇摆，还会不断旋动；尾巴翘起，表示喜悦；尾巴下垂，意味危险；尾巴不动，显示不安；尾巴夹起，说明害怕；迅速水平地摇动尾巴，象征着友好。研究人员说：“狗只对生物摇尾巴，摇尾的作用相当于人类的微笑。”

       狗特别忠诚于主人。狗于危难时刻拯救主人的新闻时常见诸报端。据研究，犬对主人的忠诚，其实是犬对母亲或群体领袖忠诚的一种转移。美国演讲家和辩论家George Graham Vest曾有一篇《向犬致敬》的法庭辩护词，高度赞美了狗的忠诚：

      “在这个自私的世界上，一个人惟一不自私的朋友，惟一不抛弃他的朋友，惟一不忘恩负义的朋友，就是他的犬。不管主人是贫困或富贵，健康或病弱，犬都会守在主人的身旁。只要能靠近主人，不管地面冰凉坚硬，寒风凛冽、大雪纷飞，它都会全然不顾地躺在主人身边。哪怕主人无食喂养，它仍会舔主人的手和主人手上因抵御这个冷酷的世界而受到的创伤。纵然主人是乞丐，它也像守护王子一样伴随着他……”

       正因为如此，狗成为人们喜爱的宠物，许多宠物狗都过上了“锦衣玉食”的生活。爱犬的人有这样一种说法：上天创造了人，看到人类如此怜弱，便为我们创造了犬。

       然而，狗普遍存在不同程度的以人类、其他动物甚至于狗自己的粪便为食的现象。也许是因为这一点，人们又一向很瞧不起狗，视狗为最下贱的动物。在一些成语、俗话中就有鲜明的体现。把走投无路时不顾后果地行动视为“狗急跳墙”，把多管闲事视为“狗拿耗子”；把人本性难改称作“狗改不了吃屎”，把人不识好歹称作“狗咬吕洞宾”；比喻心肠狠毒贪婪为“狼心狗肺”，形容不顾廉耻，到处钻营为“狗苟蝇营”；称专在后面出谋划策的人“狗头军师”，称为主人卖力的人“走狗”，称失败了的敌人“落水狗”。（根据有关材料编写）

1、“狗起源于狼，是人类最早驯化的家畜之一”中的“之一”去掉行不行？为什么？ 

     答：                                                                                                                                    

2、在介绍狗是“人类很重要的帮手”时，用的说明方法是                                                。

3、文中划线的“正因为如此”中“如此”是指                                                                     

4、再找出三个含有“狗”的成语、俗语。

     答：                                                                                             

5、文章从哪几个方面说明狗是人类忠实的朋友？

     答：                                                                                             

Anne Whitney, a sophomore(二年级学生) at Colorado State University, first had a problem taking tests when she began college. "I was always well prepared for my tests. Sometimes I studied for weeks before a test. Yet I would go in to take the test, only to find I could not answer the questions correctly. I would blank out because of nervousness and fear. I couldn’t think of the answer. My low grades on the tests did not show what I knew to the teacher ."  Another student in microbiology and similar experiences. He said ,"My first chemistry test was very difficult. Then, on the second test, I sat down to take it, and I was so nervous that I was shaking. My hands were moving up and down so quickly that it was hard to hold my pencil. I knew the material and I knew the answers. Yet I couldn’t even write them down!"

These two young students were experiencing something called test anxiety. Because a student worries and it uneasy about a test, his or her mind does not work as well as it usually does. The student can’t write or think clearly because of the extreme tension and nervousness. Although poor grades are often a result of poor study habits, sometimes test anxiety causes the low grades. Recently, test anxiety had been recognized as a real problem, not just an excuse or a false explanation of lazy students.

Special university counseling courses try to help students. In these courses, counselors try to help students by teaching them how to manage test anxiety .At some universities, students take tests to measure their anxiety. If the tests show their anxiety is high, the students can take short courses to help them deal with their tension. These courses teach students how to relax their bodies .Students are trained to become calm in very tense situations. By controlling their nervousness, they can let their minds work at ease .Learned information then comes out without difficulty on a test.

An expert at the University of California explains. "With almost all students, relaxation and less stress are felt after taking out program .Most of then experience better control during their tests. Almost all have some improvement. With some, the improvement is very great."

小题1:To "blank out" is probably______.

A．to be like a blanket

B．to be sure of an answer

C．to be unable to think clearly

D．to show knowledge to the teacher小题2:Poor grades are usually the result of _______.

A．poor hygienic(卫生的) habits

B．laziness

C．lack of sleep

D．being unable to form good study habits小题3:Test anxiety has been recognized as _______.

A．an excuse for laziness

B．the result of poor habits

C．a real problem

D．something that can’t be changed小题4:To deal with this problem, students say they want to ______.

A .take a short course on anxiety           

B read about anxiety

C. be able to manage or understand their anxiety

D take test to prove they are not anxiety

小题5:A University of California counselor said_______.

A．all students could overcome the anxiety after taking a special test anxiety program

B．almost all students felt less stress after taking a University of California counseling course

C．students found it difficult to improve even though they had taken a special test anxiety course

D．students found it easy to relax as soon as they entered a University of California counseling course

一幅256色的图像，其像素深度为（）位。

A.3

B.8

C.16

D.256

下图是人类某一家族甲种遗传病和乙种遗传病的遗传系谱图（设甲遗传病与A和a这一对等位基因有关，乙遗传病与另一对等位基因B和b有关，且甲乙两种遗传病至少有一种是伴性遗传病）。请回答有关问题：

个体8的乙种遗传病致病基因最初来源于图中的（）