题干

下列关于用高倍显微镜观察叶绿体和线粒体的实验中,说法不正确的是(  )

A:观察叶绿体时,可以用菠菜做实验材料,但是必须撕取稍带些叶肉的下表皮细胞

B:不能用菠菜叶做实验材料来观察线粒体,因为菠菜叶为绿色,影响了对实验现象的观察

C:可以用人的口腔上皮细胞做材料观察线粒体

D:健那绿可使线粒体染成灰绿色

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D

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How Important Is Fashion?

    Is looking fashionable more important than being comfortable? Many people seem to think so, judging by the things they wear. But fashion is not everything. It is more important to be a healthy and good person.

    People go to great lengths to be fashionable. Some people think they have to have a certain body type, so they go on extreme, unhealthy diets in order to change their bodies. In addition, many women wear uncomfortable fashions, such as high-heeled shoes that create blisters(水泡), tight body shapers that limit blood flow, and sticky false eyelashes. Men and women alike spend time and money on products that change their natural hair color and use hot irons and blow dryers to curl or straighten their hair. Some people spend several hours a day in front of a mirror. Is fashion important enough to spend so much time and effort on changing how you look like?

    If the purpose of fashion is to make a person feel good, it does not make sense that he or she would go through so much discomfort to be fashionable. Fashion should not come first. People should prioritize(优先考虑)being healthy and positive. What people wear does not indicate anything about their personalities. Instead of spending hours choosing a suit, perhaps you should call your friends and do something together! Instead of going on strict diets and starving, why not eat some healthy foods and then exercise? By doing these things, you can keep a healthy lifestyle and truly grow as a person.