题干

下列关于细胞核的叙述,正确的是                             (   )

A:不同的细胞内,核仁的大小和数量都是一样的

B:除少数细胞外,成熟的真核细胞都有细胞核

C:核孔是核质之间的物质任意通过的通道

D:核膜具有一个磷脂双分子层

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B

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    The latest study by the University of Florida has found that eating from smaller, less beautiful, and even paper plates will help prevent overeating. Eating with a fork instead of a spoon can help you lose weight, the researchers say. Much to their surprise, they find that putting mirrors in the dining room will also help reduce weight.

    The researchers asked 185 college students to choose a chocolate cake or a fruit salad, and evaluated the taste. Those who ate in a room with a mirror scored the taste of junk food much lower than those in a room without a mirror. But the taste of fruit salad remained the same in any case.

    Lead scientist, Dr. Ata Jami, says that a glance in the mirror tells people more than just about their physical appearance. It enables them to view themselves objectively (客观地) and helps them to judge themselves and their behavior in the same way that they judge other people.

    The mirrors were found to push people to compare and match their own behavior with accepted social standards. The researchers believe it proves that people don't want to look in the mirror when they feel they are following the social standards. When they look in the mirror with mouths full of junk food, feelings of discomfort and failure can be increased. Therefore, the presence of the mirror lowers the taste of unhealthy food.

    However, researchers say this is only the case if people select the food they are eating, because they are responsible for that choice. The researchers suggest that mirrors be placed in dining rooms and other eating spaces, so that people will start eating more healthily.