题干

关于细胞癌变、衰老的叙述,正确的是(  )

A:癌细胞的细胞膜上糖蛋白的含量比正常细胞多

B:细胞的衰老不等同于机体的衰老

C:衰老的细胞内,酶的活性降低,细胞核体积缩小

D:癌细胞与正常细胞相比,遗传物质不一定发生改变

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答案(点此获取答案解析)

B

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阅读理解

    Can you write the Chinese characters “ganga” (embarrassment) correctly? Do you know how to write characters like “tiaozhou” (broom)?

    If you can’t, you’re not alone. Nowadays, most people are typing into computers instead of writing on paper. We type Chinese characters largely according to their pronunciations. The result is to recognize characters without remembering how to write them.

China Youth Daily once did a survey among about 2,500 people, in which about 99 percent said they had once forgotten how to write a common Chinese character.

    Compared to adults, teenagers are better at writing Chinese characters because they spend more time learning and practising at school. However, the influence of digital technology cannot be ignored (忽视),according to He Yu, head of a research team for Chinese teaching at a Beijing high school.

    “Many students are obsessed (沉迷于) with digital devices such as electronic dictionaries and computers to help with their studies. Overuse of these tools will make students too lazy to think and write,” he said.

    Such worries have brought about a popular TV show titled Chinese Spelling Hero, which focuses on Chinese character writing among teenagers. In April, the Ministry of Education called for a better calligraphy (书法) education in schools. Organizations like the China Calligraphers Association are also working to train more teachers in calligraphy.

    Interestingly, calligraphy teachers can’t always avoid the effects of modem technology. Shen Bin is a calligraphy teacher at a primary school in Beijing. She admitted that it’s common for teachers like her to forget certain words.

    “The calligraphy class is also a good chance for me to remember how to write,” she said.