问题
选择题
下列哪种生物的卵具有卵壳结构（ ）
A．青蛙、蟾蜍
B．龟、蛇
C．金鱼、青鱼
D．家鸽、蚕蛾
答案
鸟类和爬行动物的卵外具有坚硬的卵壳．青蛙、蟾蜍属于两栖动物没有卵壳；龟、蛇属于爬行动物，有坚硬的卵壳；金鱼、青鱼属于鱼类没有卵壳；家鸽属于鸟类有卵壳，但蚕蛾属于昆虫没有卵壳．
故选：B
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下列哪种生物的卵具有卵壳结构（ ）
A．青蛙、蟾蜍
B．龟、蛇
C．金鱼、青鱼
D．家鸽、蚕蛾
鸟类和爬行动物的卵外具有坚硬的卵壳．青蛙、蟾蜍属于两栖动物没有卵壳；龟、蛇属于爬行动物，有坚硬的卵壳；金鱼、青鱼属于鱼类没有卵壳；家鸽属于鸟类有卵壳，但蚕蛾属于昆虫没有卵壳．
故选：B
第二卷（非选择题部分，共35分） 第四部分：写作(共二节，满分35分) 第一节：任务型阅读(共10小题；每小题1分，满分10分) 请认真阅读下面短文，并根据所读内容在文章后表格的空格处里填人最恰当的单词。注意：每个空格填1个单词。 When Percy Spencer invented the microwave, it changed the world greatly. People would no longer have to wait endless hours while cooking their food in an old-fashioned oven. Instead, using the microwave has allowed them to cook food in just seconds. According to the medical website mercola.com, just about “ninety percent of Americans have microwaves in their homes”. However, is this convenient invention as perfect as it seems? There are many reports of microwaves changing the original qualities of the food, which can cause cancer as well as changes in the body. “Electro-magnetic (电磁的) radiation harms food, and changes substances cooked in it to dangerous products,” Dr. Lita Lee – chemist, nutritionist, author and lecturer – wrote in her book, Health Effects of Microwave Radiation – Microwave Ovens (1991). However, the microwave is not only for food; microwaves are used in medicine as well. For example, it warms heating pads and used to warm blood used in transfusions (输血). Norma Levitt, a hip surgery patient in an Oklahoma hospital (1991), died after blood being heated for her transfusion was altered in the microwave. A lawsuit followed and because of this incident, blood is no longer heated in the microwave. Regardless of what has happened, big companies still claim that microwaves are great machines that have caused trouble to “few people” and have had “few consequences”. However, people should decide if saving a few minutes is more important than preventing cancerous cells from entering the body. Dr. Jonathan Wright, Medical Director of Tahoma Clinic in Renton, Washington, considers the microwave unhealthy and recommends some alternatives. “Try eating a lot of your food, like vegetables, uncooked. Ideally, at least one-third of the food in your diet should be uncooked, since this is the form that will give you the maximum amount of nutrients. If you do want to cook some food or heat up leftovers, use your stove (火炉),” he said. These alternative cooking styles may take a little time from your day, but can help you lead a healthier and more stable lifestyle. These methods will allow you to get the most nutrients from your food, as well. Health is not valued till sickness comes. In today’s fast-paced modern world, we should have more consideration towards peoples’ health.
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