题干

植物叶片中的激素主要由叶尖部位合成,植物叶片的脱落受激素的调节。图甲是叶柄离层部位的示意图,图乙是叶柄离层两侧远基端(远离茎的一侧)和近基端(靠近茎的一侧)的生长素浓度与叶片脱落关系的示意图。下列有关分析错误的是(    )

A:加速脱落叶片的叶柄内,生长素从远基端向近基端的运输需要消耗能量

B:离层区、近基端和远基端的生长素浓度决定了叶片是否脱落

C:正常生长的幼叶其叶柄远基端的生长素浓度高于近基端

D:可用较高浓度的生长素类似物溶液处理叶柄近基端来抑制叶片脱落

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D

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    In fact there are lots of videos of school bullying online every year. We feel angry with the bullies and sorry for the victims in fights and blackmails. Some middle schools and primary schools in some far counties and villages are the worst-hit parts. Nearly half the victims of bullying in middle schools choose to stay silent rather than ask for help or ways to solve the problem, China Youth Daily reported.

    There is a study on junior middle school bullying made by the China Women's University. It showed that 48.9 percent of the students never asked for help after being bullied. And the study also told us 52.6 percent kept silent because they were afraid of “losing face among schoolmates”.

    The China Youth and Children Research Center made a survey of 5,864 primary and middle school percent of students suffered bullying, while 6.1 percent were often bullied by senior schoolmates.

    Cases of violence between boys and girls totaled 85 percent of all school bullying, the report said. Violence between girls accounted for as much as 32.5percent of the total. Unlike direct arguments usually seen between boys, the violence between girls more often took the form of insults, which terribly caused victims have strong feelings, it was added.

    A study published by the Beijing High People's Court showed that 68 percent of offenders attacked their schoolmates in a cruel manner and nearly 60 percent of school violence cases were caused by small matters, Legal Daily said.

    Earlier, Tang Jun of Renmin University of China told reporters that the social risks of school bullying have been given too little care. We should train our teachers to deal with school bullying, improve their skills of preventing it, and help the victim students to recover physically and mentally. At the same time, students and their parents should know the school's rules about bullying and what they should do if it happens. Second, children should be taught to stand up for themselves. They should try to solve problems by talking them out. Children should tell someone if they are being picked on. Third, parents should look for warning signs of bullying. We must pay more attention to it and try our best to solve it.