题文
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 color. 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?
Which works harder depends on whether you are 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 energy 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-ups?
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. 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（旋转） 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 of 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 animal 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 color of blood in a vein near the surface of the skin?A．Blue. B．Light yellow.C．Red. D．Dark reddish purple.小题2:Why do some old people look a little shrunken as they age?A．Because their spine is in active use.B．Because they are more easily affected by gravity.C．Because they keep growing backwards.D．Because their spine becomes more bent.小题3:Which of the following statements about our brain is true?A．In the long run, our brain probably works harder than our heart.B．When our brain senses the spinning, we will fell dizzy.C．The brains of the other mammals are as complex as those of humans.D．Our feelings and emotions come from the most developed area in our brain.小题4:What is the main purpose of the selection?A．To give advice on how to stay healthy.B．To provide information about our body.C．To challenge new findings in medical research.D．To report the latest discoveries in medical science. 题型：未知 难度：其他题型
答案
小题1:D
小题2:D
小题3:A
小题4:B
解析
你知道我们身体的一些秘密吗？比如血液是红色的，但为什么静脉看起来却是绿色的？等等问题，读完本篇你就会找到答案。
小题1:细节题：根据第一段第二句Although blood looks red when it’s outside the body, when it’s sitting in the vein near the surface of the skin, it’s more of a dark reddish purple color.很容易判断出皮肤表面的静脉是暗红色的，选Ｄ。
小题2:细节题：根据第四段最后一句Or, more often, become more bent and curved.可以判断他们的脊柱是弯曲的，选Ｄ。
小题3:排除题：根据第二段最后一句But in the long run, your brain probably tips it, because even when you’re sitting still your brain is using twice as much energy as your heart, and it takes four to five times as much blood to feed it.可知Ａ项正确。通过第五段最后一句But when you suddenly stop spinning the system goes out of control, and your brain thinks you’removing while you’re not可知当我们突然停止旋转时才会感到眩晕，所以Ｂ项错误；通过第六段最后一句But since human feelings also involve other, newer bits of the brain, we feel more complex emotions than any other animal on this planet.可知Ｃ，Ｄ两项错误。
小题4:写作意图题：本篇的写作意图就是让我们了解我们的身体，为我们提供一些基本的信息，故Ｂ项正确。
考点
据考高分专家说，试题“Below is a selection.....”主要考查你对 [科教类阅读 ]考点的理解。科教类阅读
科教类阅读的概念：
科教类阅读主要考查考生对书面语篇的整体领悟能力和接受及处理具体信息的能力。试题的取材，密切联系当前我国和世界经济、科技等方面的变化，有关数据的来源真实可信。
科教类文章阅读技巧：
一、材料特点：
这类文章的总体特点是：科技词汇多，句子结构复杂，理论性强，逻辑严谨。具体说来它有以下几个特点：
1、文章中词汇的意义比较单一、稳定、简明，不带感情色彩，具有单一性和准确性的特点。这类文章通常不会出现文学英语中采用的排比、比喻、夸张等修辞手法，一词多义的现象也不多见。
2、句子结构较复杂，语法分析较困难。为了描述一个客观事物，严密地表达自己的思想，作者经常会使用集多种语法现象于一体的长句。
3、常使用被动语态，尤其是一些惯用被动句式。
二、命题特点：
科普类阅读的主要命题形式有事实细节题、词义猜测题、推理判断题以及主旨概括题等，其中推理判断题居多。
三、应对策略：
1、要想做好科普英语阅读理解题，同学们就要注意平时多读科普知识类文章，学习科普知识，积累常见的科普词汇，从根本上提高科普英语的阅读能力。
2、要熟悉科普类文章的结构特点。科普类文章一般由标题(Head line)，导语(Introduction)，背景(Back ground)，主体(Main body)和结尾(End)五部分构成。标题是文章中心思想高度而又精辟的概括，但根据历年的高考情况来看，这类阅读理解材料一般不给标题，而要同学们选择标题。导语一般位于整篇文章的首段。背景交待一个事实的起因。主体则对导语概括的事实进行详细叙述，这一部分命题往往最多，因此，阅读时，同学们要把这部分作为重点。结尾往往也是中心思想的概括，并与导语相呼应，命题者常在此要设计一道推理判断题。
3、在进行推理判断时，同学们一定要以阅读材料所提供的科学事实为依据，同时所得出的结论还应符合基本的科普常识。
科普类阅读应试策略：
【命题趋势】
阅读理解题主要考查考生对书面语篇的整体领悟能力和接受及处理具体信息的能力。试题的取材，密切联系当前我国和世界经济、科技等方面的变化，有关数据的来源真实可信。因此科普知识类文章是每年的必考题。分析历年的科普类文章我们不难发现以下特点：
1、文章逻辑性强，条理清楚，语法结构简单，用语通俗。
2、文章内容注重科技领域的新发现。内容新颖，从而使文章显得陌生，内容抽象复杂。
3、命题方面注意对具体细节的准确理解和以之为依据的推理判断。
4、以人们的日常行为或饮食健康入手，探讨利弊，诠释过程，阐述概念。
【应试对策】
许多考生在考试时感到困惑的是：为什么一些没有超越中学语法和词汇范围的篇章，读起来却不能正确理解，或者要花费很多时间才能读懂呢？这种现象的产生与阅读方法有很大的关系。例如，有的考生在考试时一见到文章就立刻开始读，结果读了半天，还不知道短文讲的是什么，试题要求了些什么，结果浪费了大量的时间，而阅读效果并不好。那么，怎样读效果才好呢？任何一种阅读方法或技巧的使用，都是由篇章特点和试题本身的要求决定的，应根据不同的体裁和试题要求采取不同的策略。
1、浏览。浏览的主要目的就是确定文章的体裁。如果文章属于人物传记、记叙文、故事、科普小品和有关社会文化、文史知识的文章，一般来说，应该先看看文章的试题考查内容，对题目类型做到心中有数，针对不同问题，在通读时有粗有细地去阅读，这样不仅能把握篇章的基本结构和逻辑线索，也能做好有关具体事实信息考查的试题。
2、挖掘寓意，掌握中心思想，推出结论。任何文章，作者在行文时都有一定的写作目的和主要话题。在通读篇章时应该吃透作者的写作意图，抓住文章的主题句，充分发挥自己的想象力和概括力，作出对中心思想的归纳和结论的推断。
3、把握篇章结构，利用上下文进行推测。高考中的阅读理解篇章往往是一个较完整的短文，其结构、思想，前后上下连贯统一。考试时应充分利用这一特点推测一些生词、短语在句中的含义，切莫盲目孤立猜测。
4、综观全篇，前后呼应。这是阅读理解的最后一步，在做完阅读理解题后，要立足于文章整体，再迅速读一遍短文，短文中的问题和答案的设置前后都是相关联的，有着一定的连续性，体现着文章的基本脉络。
