某同学发现了一株花色奇特的杜鹃花，于是采摘了部分枝条，打算用扦插的方式进行繁殖。下列关于该实验的叙述，不正确的是[ ]
A．采摘的枝条中，芽较多、较嫩的枝条相对来说更容易生根
B．生长素促进生根的效果与生长素处理枝条的时间长短成正比
C．生长素类似物有一定的毒性，实验结束后应妥善处理废液
D．可发现两个不同的生长素浓度，促进根生长的效果相同
答案：B
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| Today the problem of environment has become more and more serious. Every day, every hour, the air, forests, soil, oceans and fresh 1 are becoming dirtier and dirtier. There are two 2 for the problem: the excessive (过度) use of natural resources and pouring a lot of 3 waste in the course of production. Yet, man 4 great progress in environmental protection. Scientists and inventors are trying to develop 5 engines for automobiles. Governments of many countries have made 6 to protect the natural resources. More and more people have realized the importance of environmental protection and are doing what they can to protect our surroundings. Still more ways 7 to solve the problem. People should be educated in 8 modern methods to protect the environment and learn to make clever use of recycling our natural resources. The government of all 9 should take ways to fight against pollution _ 10 _ protecting the environment is not only protecting our home but also the civilization (文明) of the humankind. | |||
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