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问题 单项选择题

行为模式指个人和他人，或个人和团体相互作用表现出来的行为。A型行为模式与冠心病的发病有着密切关系。在下列特征中，不属于A型行为模式的是（）

A.有强烈事业心

B.多愁善感

C.急躁易怒

D.竞争性强

E.急于求成

答案

参考答案：B

填空题

（1）用化学方程式表示下列反应，并注明反应类型．

①镁带在空气中燃烧，化学方程式______，反应类型______．

②电解水化学方程式______，反应类型______．

③氢气还原氧化铜化学方程式______，反应类型______．

（2）市售紫葡萄的表面常附有一些浅蓝绿色的斑点，它是为了防治霉菌而喷洒的农药波尔多液．波尔多液常用氢氧化钙和硫酸铜来配制．配制的化学方程式______．反应类型______．
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单项选择题

Lichens may grow on the bark of a tree in a steaming tropical rain forest, on the bricks of big city buildings, on rocks in hot springs, on wind-swept mountaintops, and in the driest desserts. In the arctic, they provide the principal food for caribou, and they are one of the few plants that grow in Antarctica. They are pioneers, appearing in barren rocky areas and starting the formation of soil in which mosses, then ferns, and then other plants can take root.
Lichens are a partnership of two plants — fungi and algae. The lichen body is made up of a network of fungal strands. In the upper layers of these grow groups of algae. The two organisms live together to the benefit of both, a relationship known as symbiosis. The fungi provide support, absorb water, and shelter the tender algae from direct sunlight. The algae carry on photosynthesis and provide the fungi with food. The algae can live independently and are recognizable as a species that grows alone. The fungi, on the other hand, cannot live apart from their partners. They can be placed in known classes of fungi but are unlike any species that lives independently.
So definite are the form, color, and characteristics of these double organisms that for hundreds of years, they were classified as one. More than 15,000 "species" were named. If these organisms are classified as separate species, it is difficult to fit them into the existing system of classification. But if they are classified separately, these species of fungi seem rather strange. Lichens are a splendid example of the difficulties faced by taxonomists in classifying species.

Which of the following can be inferred about the effect of direct sunlight on lichens

A．It damages the algae.
B．It helps the fungi absorb water.
C．It is required for the algae to carry on photosynthesis.
D．It destroys the fungi.
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