高千伏摄影特点的叙述，错误的是（） A.获得低对比，层次丰富的X线照片 B.缩短曝光

Below is a selection from a popular science book.

If blood is red, why are veins（静脉）blue?

Actually, veins are not blue at all. They are more of a clear, yellowish colour. Although blood looks red when it’s outside the body, when it’s sitting in a vein near the surface of the skin, it’s more of a dark reddish purple colour. At the right depth, these blood-filled veins reflect less red light than the surrounding skin, making them look blue by comparison.

Which works harder, your heart or your brain?

That kind of depends on whether you’re busy thinking or busy exercising. Your heart works up to three times harder during exercise, and shifts enough blood over a lifetime to fill a supertanker. But, in the long run, your brain probably tips it, because even when you’re sitting still your brain is using twice as much as your heart, and it takes four to five times as much blood to feed it.

Why do teeth fall out, and why don’t they grow back in grown-up?

Baby (or “milk”) teeth do not last long; they fall out to make room for bigger, stronger adult teeth later on. Adult teeth fall out when they become damaged, decayed and infected by bacteria. Once this second set of teeth has grown in, you’re done. When they’re gone, they’re gone. This is because nature figures you’re set for life, and what controls regrowth of your teeth switches off.

Do old people shrink as they age?

Yes and no. Many people do get shorter as they age. But, when they do, it isn’t because they’re shrinking all over. They simply lose height as their spine(脊柱)becomes shorter and more curved due to disuse and the effects of gravity（重力）. Many (but not all) men and women do lose height as they get older. Men lose an average of 3—4 cm in height as they age, while women may lose 5 cm or more. If you live to be 200 years old, would you keep shrinking till you were, like 60 cm tall, like a little boy again? No, because old people don’t really shrink! It is not that they are growing backwards—their legs, arms and backbones getting shorter. When they do get shorter, it’s because the spine has shortened a little. Or, more often, become more bent and curved.

Why does spinning make you dizzy(眩晕的)?

Because your brain gets confused between what you’re seeing and what you’re feeling. The brain senses that you’re spinning using special gravity-and-motion-sensing organs in your inner ear, which work together with your eyes to keep your vision and balance stable. But, when you suddenly stop spinning the system goes out control, and your brain thinks you’re moving while you’re not!

Where do feelings and emotions come from?

Mostly from an ancient part of the brain called the limbic system. All mammals have this brain area—from mice to dogs, cats, and humans. So all mammals feel basic emotions like fear, pain and pleasure. But since human feelings also involve other, newer bits of the brain, we feel more complex emotions than any other animals on the planet.

If exercise wears you out, how can it be good for you?

Because our bodies adapt to everything we do to them. And as far as your body is concerned, it’s “use it, or lose it”! It’s not that exercise makes you healthy; it’s more that a lack of exercise leaves your body weak and easily affected by disease.

小题1:What is the colour of blood in a vein near the surface of the skin?

A．Blue

B．Dark reddish purple

C．Red

D．Light yellow小题2:Why do some old people look a little shrunken as they age?

A．Because their spine become more bent.

B．Because they are more easily affected by gravity.

C．Because they keep growing backwards.

D．Because their spine is in active use.小题3:Which of the following statements about our brain is true?

A．The brains of the other mammals are as complex as those of humans.

B．When our brain senses the spinning, we will feel dizzy.

C．In the long run, our brain probably works harder than our heart.

D．Our feelings and emotions come from the most developed area in our brain.小题4:. In this article, we can know except _____.

A．it takes four to five times as much blood to feed our brain as to feed our heart.

B．when adult teeth are gone, they cannot grow back.

C．the reason why spinning make us dizzy.

D．how we can grow taller.小题5: What is the main purpose of the selection?

A．To give advice on how to stay healthy.

B．To report the latest discoveries in medical science.

C．To challenge new findings in medical research.

D．To provide information about our body.

Ａ．(选修模块3-3）（12分）

（1）下列四幅图的有关说法中正确的是      　　

A．分子间距离为r₀时，分子间不存在引力和斥力

B．水面上的单分子油膜，在测量油膜直径d大小时可把他们当做球形处理

C．食盐晶体中的钠、氯离子按一定规律分布，具有空间上的周期性

D．猛推木质推杆，气体对外界做正功，密闭的气体温度升高，压强变大

（2）已知某物质摩尔质量为M，密度为ρ，阿伏加德罗常数为N_A，则该物质的分子质量为      ，单位体积的分子数为      ． 

（3）如图，一定质量的理想气体从状态A经等容过程变化到状态B，此过程中气体吸收的热量Q=6.0×10²J，

求：

①该气体在状态A时的压强；

②该气体从状态A到状态B过程中内能的增量。

B．(选修模块3-４）（12分）

（1）下列四幅图的有关说法中正确的是   　  

A．由两个简谐运动的图像可知：它们的相位差为/2或者

B．当球与横梁之间存在摩擦的情况下，球的振动不是简谐运动

C．频率相同的两列波叠加时，某些区域的振动加强，某些区域的振动减弱

D．当简谐波向右传播时，质点A此时的速度沿y轴正方向

（2）1905年爱因斯坦提出的狭义相对论是以狭义相对性原理和           这两条基本假设为前提的；在相对于地面以0.8c运动的光火箭上的人观测到地面上的的生命进程比火箭上的生命进程要　　　（填快或慢）。

（3）如图所示，△ABC为等腰直角三棱镜的横截面，∠C=90°，一束激光a沿平行于AB边射入棱镜，经一次折射后射到BC边时，刚好能发生全反射，求该棱镜的折射率n和棱镜中的光速。

C．(选修模块3-5）（12分）

（1）下列说法正确的是

A．某放射性元素经过19天后，余下的该元素的质量为原来的1/32，则该元素的半衰期为 3.8天

B．a粒子散射实验说明原子核内部具有复杂结构

C．对放射性物质施加压力，其半衰期将减少

D．氢原子从定态n=3跃迁到定态n= 2，再跃迁到定态n = 1，则后一次跃迁辐射的光的波长比前一次的要短

（2）光电效应和       都证明光具有粒子性，      提出实物粒子也具有波动性。

（3）如图所示,水平光滑地面上依次放置着质量均为m ="0.08" kg的10块完全相同的长直木板。质量M =" 1.0" kg、大小可忽略的小铜块以初速度v₀="6.0" m/s从长木板左端滑上木板，当铜块滑离第一块木板时，速度大小为v₁="4.0" m/_S。铜块最终停在第二块木板上。取g="10" m/s²，结果保留两位有效数字。求：

①第一块木板的最终速度

②铜块的最终速度

物种的减少对人类的影响是  [ ]

A．减少人类的食物来源

B．危害人类的身体健康

C．破坏大自然的生态平衡

D．危及人类的生存和发展

卡夫卡生活在世界形势激烈动荡的时期，他看到西方社会的内在危机，但无法找到解决这些危机的出路。他孤独、苦恼，______，心情矛盾，他的小说大多描写人的孤独和犯罪心理，或人在重重压迫下改变不了自己的命运以致异化的现象，内容______。
依次填入画横线部分最恰当的一项是( )。

A．自怨自艾 怪诞离奇
B．垂头丧气 荒谬绝伦
C．怨天尤人 光怪陆离
D．愤世嫉俗 荒诞不经

患者，男，12岁。间断咳嗽6月，左膝痛2月，偶发热，最高体温T38.0℃。查体：消瘦、跛行。左膝肿胀，局部皮温正常，浮髌试验阳性，屈曲功能稍受限。右膝活动正常。查血常规：WBC1.0×10⁹/L，N0.50，L0.47。ESR 67mm/h。

该病例首选的检查是

A．左膝关节穿刺抽液检查

B．左膝关节CT

C．左膝关节活组织检查

D．胸部X线片