题干

红苋菜细胞的液泡内含有呈紫红色的花青素.将红苋菜的叶片切成小块后放入水中,水的颜色无明显变化.若进行加热,随着水温的升高,水的颜色逐渐变红.其原因是(    )

A:细胞壁在加温后受到破坏

B:水温升高,花青素的溶解度加大

C:加温使细胞膜和液泡膜失去了控制物质进出的功能

D:加温使花青素分子的活性加大而容易透过细胞膜

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C

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    What are some tips on becoming a writer?

    ____

    Most writers read whatever books they can find because they love to lose themselves in them. They like the sounds of language and the way that reading a good description can feel as satisfying as winning a baseball game or eating a banana split.

    ____

    It's easy to forget a good idea if you do not write it down immediately. If you get in the habit of carrying a notebook with you everywhere you go, you can write down anything you want to remember. When you are talking to friends in the cafe or waiting for the bus, something might spark an idea for a character or a scene in a story.

    ____

    Nearly all writers agree that writers must write. It doesn't matter if you feel like you have nothing to say; the important thing is that you write every single day. Sometimes, you need to give yourself permission to write things which won't be your best work.

    ____

    Do you have any friends who enjoy writing? Think about starting a writing group with other people who have similar interests. It helps to have the support of other writers. You will also receive valuable feedback, or suggestions, about how to make your work better.

    ____

    If you decide that you would like to send your work for publication, make sure to do your research. If you are sending your writing to a magazine, look through old ones. Does it seem like your writing fits in with the other stories or articles? That is the homework for you after writing.

A. Join or start a writing group.

B. Read everything you can.

C. Write every day.

D. Keep a notebook.

E. Stay active.

F. Do your homework.