Botany
Botany, the study of plants, occupies a peculiar position in the history of human knowledge. For many thousands of years it was the one field of awareness about which humans had anything more than the vaguest of insights. It is impossible to know today just 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 a great many other purposes. Tribes living today in the jungles of the Amazon recognize literally hundreds of plants and know many properties of each. To them, botany, as such, has no name and is probably not even recognized as a special branch of knowledgeat 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.
11月19日雅思阅读的试题(网友版)
12月10日雅思口语真题的解析
11月21日雅思写作的回忆(网友版)
11月24日的雅思口语真题的回忆
11月17日雅思口语的真题解析
11月12日雅思听力真题的机经(网友版)
11月21日雅思阅读的真题解析
11月12日雅思听力试题的真题
11月21日的雅思的听力真题答案回忆
11月26日雅思写作试题真题的回忆(环球版)
2014年11月12日雅思听力真题回忆
12月10日雅思考试写作的范文
11月28日雅思写作的回忆(网友版)
11月10日雅思写作的回忆(网友版)
11月21日的雅思写作真题解析
11月12日雅思口语真题的解析
11月28日雅思口语的回忆(网友版)
11月21日的雅思阅读真题及解析
12月12日雅思考试真题的机经及答案解析
11月17日雅思阅读的回忆(网友版)
11月21日的雅思阅读真题机经(网友版)
12月10日雅思阅读的回忆(网友版)
11月21日雅思的听力真题解析
11月12日雅思口语试题的真题(版)
11月28日的雅思阅读回忆(网友版)
11月10日雅思阅读d 真题回忆
12月12日雅思口语d 回忆(网友版)
11月10日雅思听力的回忆(网友版)
11月24日雅思口语的真题解析
12月12日雅思阅读的回忆(网友版)
| 不限 |
| 英语教案 |
| 英语课件 |
| 英语试题 |
| 不限 |
| 不限 |
| 上册 |
| 下册 |
| 不限 |