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【单选题】
Plants and Mankind Botany, the study of plants, occupies a peculiar position in the history of human knowledge. We don't know what our Stone Age ancestors knew about plants, but from what we can observe of preindustrial societies that still exist, a detailed learning of plants and their properties must be extremely ancient. This is logical. Plants are the basis of the food pyramid for all living things, even for other plants. They have always been enormously important to the welfare of people, not only for food, but also for clothing, weapons, tools, dyes, medicines, shelter, and many other purposes. Tribes living today in the jungle of the Amazon recognize hundreds of plants and know many properties of each. To them botany has no name and is probably not even recognized as a special branch of' knowledge' at all. Unfortunately, the more industrialized we become the farther away we move from direct contact with plants, and the less distinct our knowledge of botany grows. Yet everyone comes unconsciously on an amazing amount of botanical knowledge, and few people will fail to recognize a rose, an apple, or an orchid. When our Neolithic ancestors, living in the Middle East about 10,000 years ago, discovered that certain grasses could be harvested and their seeds planted for richer yields the next season, the first great step in a new association of plants and humans was taken. Grains were discovered and from them flowed the marvel of agriculture: cultivated crops. From then on, humans would increasingly take their living from the controlled production of a few plants, rather than getting a little here and a little there from many varieties that grew wild and the accumulated knowledge of tens of thousands of years of experience and intimacy with plants in the wild would begin to fade away. It is logical that a detailed learning of plants and their properties must be extremely ancient.
A.
Right
B.
Wrong
C.
Not mentioned
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参考答案:
举一反三
【单选题】经减数分裂形成花粉粒的是( )。
A.
孢原细胞
B.
小孢子母细胞
C.
大孢子母细胞
D.
极核
【单选题】一个小孢子母细胞或大孢子母细胞经过减数分裂形成( )个子细胞。
A.
1
B.
2
C.
4
D.
8
【单选题】模板、支架和拱架的拆除,做法错误的是( )。
A.
非承重侧模板应在混凝土强度能保证其表面及棱角不致因拆模而受损坏时方可拆除,一般应在混凝土抗压强度达到2.5MPa时方可拆除侧模板
B.
当构件跨度不大于4m时,在混凝土强度符合设计强度标准值的50%的要求后,方可拆除
C.
当构件跨度大于4m时,在混凝土强度符合设计强度标准值的75%的要求后,方可拆除
D.
跨径小于20m的小拱桥,宜在拱上建筑全部完成后卸架
【判断题】定位焊时,由于焊缝长度较短,所以应该选择较小的线能量
A.
正确
B.
错误
【单选题】Martin: Is there anything else to discuss? Jenny:__________ . I guess. Martin: Then, let‘ s call it a day.
A.
Yes, just one more thing
B.
Oh, I' m not sure
C.
Yes, still a lot
D.
No, that' s all
【判断题】定位焊时,由于焊缝长度较短所以应该选择较小的焊接线能量。
A.
正确
B.
错误
【单选题】我要为找工作而努力学习和实践,提高综合能力。——属于自我意识哪部分?
A.
自我认知
B.
自我体验
C.
自我调控
【简答题】连词成句。 1. white, snow, is, and, cold (.) _________________________________________________ 2. hot, is, sun, the (.) _________________________________________________ 3. is, it, day, what (?) __________...
【单选题】定位焊时,由于焊缝长度较短所以应该选择较小的焊接线能量。( )
A.
正确
B.
错误
【单选题】“若微寒者,桂枝去芍药加附子汤主之”之“微寒”指
A.
轻微恶寒
B.
指头寒
C.
脉微恶寒
D.
胸微恶寒
E.
脉微弱
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