题干

根尖的成熟区是植物吸收水分的主要部位,其主要原因是(    )

A:成熟区有大量的根毛

B:成熟区位于根尖的顶端

C:成熟区的细胞形似正方体

D:成熟区的细胞体积很小

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A

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    At what age does a child became an adult?____Here are a few examples.

    First, in some North American Indian culture, a boy became a man around the age of 13. At that time, he would go into the woods alone, without food or water, for several days.____Girls became adult women as soon as they were old to have babies, also around the age of 12 or 13.

    In the Jewish religion, children spend years studying their history and religion. Then, at age of 13 for boys and 12 for girls, they go through an important religious ceremony.____

    In Japan today, young people become legal adult at age 20. Each year on January 15th, they celebrate “Coming-of-Age Day”, when the 20-year-olds in a town are invited to attend to special ceremony.____

    Finally, in the United States, the passage into adulthood takes several years. American teenagers look forward to their 16th birthday because in most states that is the age when can get a driver's license. The legal age of adulthood is 18, when Americans can vote, get married and work full-time. However, they must wait until age 21 to buy alcohol.____

A. Many people celebrate their 21st birthday by having a drink with friends in a bar.

B. It's hard to answer the question.

C. The answer depends on your culture or religion.

D. From that day, they are adults, and they become responsible for their own religious development.

E. When he returned safely, he became an adult man.

F. The teenagers are not allowed to drink alcohol.

G. They wear traditional clothes, listen to speeches and visit old friends.