题干

下列关于植物生长素生理作用的叙述,错误的是

C:幼嫩的细胞比老一些的细胞对生长素反应灵敏

A:适宜浓度的生长素可促进扦插的枝条生根

B:植物的茎在背光的一侧生长素分布很少,细胞分裂快

D:顶芽产生的生长素运输到侧芽,使其生长素浓度较高,抑制其生长,引起顶端优势

上一题 下一题 0.0难度 选择题 更新时间:2019-11-19 01:31:19

答案(点此获取答案解析)

B

同类题5

用括号里所给动词的适当形式填空。

    I recently heard a story about a famous scientist. Because of his great achievements, he was thought to be more creative than the ordinary person. When he ____ (ask) why he was able to do this, he gave the answer. It all came from an experience with his mother when he was about two years old. “I tried to get a bottle of milk from the fridge when I lost the bottle and it fell, spilling(溢出)the milk all over the floor — a sea of milk! I was frightened and I didn’t know what to do!” he said.

    His mother heard the noise and got into the kitchen. “I ____ (consider)how to explain all this to you, mom.” He said. Instead of ____ (punish) him, she said, “Robert, what a great mess(杂乱) you have made! I ____ (not see) such a huge sea of milk before! Well. since the milk has already been spilled, would you like to play in the milk for a while? We ____ (clean) it up after that.” Indeed, he did so. After a few minutes, his mother said, “You know, Robert, whenever you make a mess like this, finally you have to clean it up.” He used a sponge(海绵) and together they cleaned up the spilled milk. His mother then said, “You know, you ____(fail)in how to successfully carry a big milk bottle with two tiny hands just now. Let’s go out in the yard and fill the bottle with water to see if you can find a way to carry it.” Then the little boy learned that if he grasped (抓紧) the bottle at the top near the lip with both hands, he could carry it without dropping it. What a wonderful lesson!