题干

下列关于胚胎工程的叙述,正确的是(  )

A:经激素处理卵巢,使其超数排卵可获得成熟的卵细胞

B:精子在精巢中发育成熟,在附睾中获能

C:胚胎移植的最适宜时期是发育到8细胞以上的胚胎,如早期囊胚

D:分割后的胚胎或细胞必须在体外培养到囊胚阶段才能移植到受体内

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C

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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.