题干

人在15℃环境中和5℃环境中穿的衣服一样多时,体温是恒定的,而且在这两种环境中既不出汗也无寒颤,这时体温的调节主要通过(  )

A:增减产热量

B:调节皮肤血管口径

C:立毛肌收缩或舒张

D:拱肩缩背以保温或伸展肢体以散热

上一题 下一题 0.0难度 选择题 更新时间:2019-05-06 09:23:25

答案(点此获取答案解析)

B

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    If English means endless new words, difficult grammar and sometimes strange pronunciation, you are wrong. Haven't you noticed that you have become smarter since you started to learn a language?

    According to a new study by a British university, learning a second language can lead to an increase in your brain power. Researchers found that learning other languages changes grey mater. This is the area of the brain which processes information. It is similar to the way that exercise builds muscles.

    The study also found the effect is greater when the younger people learn a second language. A team led by Dr. Andrea Mechelli, from University College London, took a group of Britons who only spoke English. They were compared with a group of bilinguals who had learnt a second language before the age of five, as well as a number of later learners.

    Scans showed that grey mater density(密度) in the brain was greater in bilinguals than in people without a second language.

    “Our findings suggest that the structure of the brain is changed by the experience of learning a second language,” said the scientists. It means that the change itself increases the ability to learn.

    Professor Dylan Vaughan Jones of the University of Wales, has researched the link between bilingualism and maths skills. “Having two languages gives you two windows on the world and makes the brain more flexible,” he said. “You are actually going beyond language and have a better understanding of different ideas.”

    The findings were matched in a study of native Italian speakers who had learned English as a second language between the ages of two and thirty-four. Reading, writing, and comprehension were all tested. The results showed that the younger they started to learn, the better. “Studying a language means you get an entrance to another world,” explained the scientists.