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问题 填空题

自然界中的碳循环对人类活动有重大影响．

（1）CO2经光合作用转化为有机物，该过程将太阳能转化为　       　能．

（2）葡萄糖（C6H12O6）完全燃烧的化学方程式为　                     　．

（3）人呼吸作用产生的CO2若不能及时排出，滞留在血液中会使血液的pH　  　（填“不变”、“变大”或“变小”）．

答案

（1）化学；（2）C6H12O6+6O26CO2+6H2O；（3）变小．

题目分析：（1）CO2经光合作用转化为有机物，该过程将太阳能转化为化学能．

（2）葡萄糖（C6H12O6）完全燃烧生成二氧化碳和水，反应的化学方程式为：C6H12O6+6O26CO2+6H2O．

（3）pH值小于7呈酸性，且pH越小，酸性越强；如果人体中的CO2不能顺利的排出体外，二氧化碳和水反应生成碳酸，血液的酸性增强，则血液的pH会变小．

点评：本题难度不大，掌握化学反应时的能量变化、化学方程式的书写、二氧化碳的化学性质、溶液的酸碱性和溶液pH大小之间的关系是正确解题的关键．

单项选择题 A1/A2型题

有关体感诱发电位的主要成分不包括是（）。

A.臂丛神经电活动

B.近段臂丛和颈神经电活动

C.在颈部放置的电极可记录到近段臂丛和颈髓楔束传入的电信号活动

D.a颈髓的突触后活动

E.脊髓背柱电活动
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单项选择题

When an invention is made, the inventor has three possible (1) of action open to him: he can give the invention to the world by publishing it, keep the idea (2) , or patent it.

A (3) patent is the result of a bargain (4) between an inventor and the state, hut the inventor gets a limited period of monopoly and publishes full details of his invention to the public after that period (5) .

Only in the most exceptional circumstances (6) the lifespan of a patent (7) to alter this normal process of events.

The longest extension ever (8) was to Georges Valensi; his 1939 patent for color TV receiver circuit was extended until 1971 because for most of the patent’s normal life there was no color TV to (9) and thus no hope for reward for the invention.

Because a patent remains permanently (10) after it has terminated, the shelves of the library attached to the (11) office contain details of literally millions of ideas that are free for anyone to use and, if (12) than half a century, sometimes even repatent. Indeed, patent experts often advise anyone (13) to avoid the high cost of conducting a search through (14) patents that the one sure way of violation of any other inventor’s right is to plagiarize a dead patent. Likewise, because publication of an idea in any other form (15) invalidates further patents on that idea, it is traditionally (16) to take ideas from other areas of print. Much modern technological advance is (17) on these presumptions of legal security.

Anyone closely (8) in patents and inventions soon learns that most "new" ideas are, in fact, as old as the hills. It is theft reduction to commercial practice, either through necessity or dedication, or through the availability of new technology, (19) makes news and money. The basic patent for the theory for magnetic recording dates back to 1886. Many of the original ideas behind television originate (20) the late 19th and early 20th century. Even the Volkswagen rear engine ear was anticipated by a 1904 patent for a cart with the horse at the rear.

15（）

A.temporarily

B.suddenly

C.permanently

D.sharply
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