1831年.英国著名物理学家______发现了电磁感应现象,导致了______,从而开辟了人类电的时代.
在奥斯特发现了电流的磁效应后,很多科学家致力于寻找磁场与电流的关系,英国物理学家法拉第经十年的不懈努力,终于发现了闭合电路中的部分导体在磁场中做切割磁感线运动时会产生感应电流,即电磁感应现象.后人根据这一现象制造了发电机.
故答案为:法拉第,发电机.
1831年.英国著名物理学家______发现了电磁感应现象,导致了______,从而开辟了人类电的时代.
在奥斯特发现了电流的磁效应后,很多科学家致力于寻找磁场与电流的关系,英国物理学家法拉第经十年的不懈努力,终于发现了闭合电路中的部分导体在磁场中做切割磁感线运动时会产生感应电流,即电磁感应现象.后人根据这一现象制造了发电机.
故答案为:法拉第,发电机.
About fifty years ago, plant physiologists set out to grow roots by themselves in solutions in laboratory flasks. The scientists found that the nutrition of isolated roots was quite simple. They required sugar and the usual minerals and vitamins. However, they did not require organic nitrogen compounds. These roots got along fine on mineral inorganic nitrogen. Roots are capable of making their own proteins and other organic compounds. These activities by roots require energy, of course. The process of respiration uses sugar to make the high energy compound ATP, which drives the biochemical reactions. Respiration also requires oxygen. Highly active roots require a good deal of oxygen. The study of isolated roots has provided an understanding of the relationship between shoots and roots in intact plants. The leaves of the shoots provide the roots with sugar and vitamins, and the roots provide the shoots with water and minerals. In addition, roots can provide the shoots with organic nitrogen compounds. This comes in handy for the growth of buds in the early spring when leaves are not yet functioning. Once leaves begin photosynthesizing, they produce protein, but only mature leaves can "export" protein to the rest of the plant in the form of amino acids. |
According to the passage, what is ATP
A.A biochemical process.
B.The tip of a root.
C.A chemical compound.
D.A type of plant cell.