2. 专升本
  3. To preserve food, the growth of bacteria (细菌) must be controlled. Water, warmth, and food are all needed for bacteria to become

To preserve food, the growth of bacteria (细菌) must be controlled. Water, warmth, and food are all needed for bacteria to become

admin2019-03-27  118
问题     To preserve food, the growth of bacteria (细菌) must be controlled. Water, warmth, and food are all needed for bacteria to become strong and healthy. Some kinds of bacteria need air, but other kinds grow only when air is absent. Extremes of temperature, either hot or cold, can kill bacteria.
    Before refrigerators were invented, freezing and cooling were limited by the cold climate. In warmer regions, food was cooled by putting it in the shade, in cold water from the well, or in pits (坑) in the ground.
    Cooking will usually kill bacteria if the temperature is high enough and the high temperature lasts long enough. Certain methods of cooking remove water, and this aids in preserving food. Drying is the oldest and most common method of preserving food. Food can be dried by the sun, by heat or by combination of the two.
    Salt was used by many hunting people. When people began to eat vegetables, salt became a needed part of their life. Salt helps to preserve food because it slows or stops bacteria to grow. Other chemicals besides salt are used in preserving food. Some people oppose the use of chemicals in food. They say that these chemicals may harm people if the chemicals can harm bacteria.
Why are many people against the use of chemicals to preserve food?
选项 A、Because chemicals are not necessary for preserving food.
B、Because a small quantity of bacteria in food is good for the body.
C、Because those chemicals that kill bacteria may not be good for people.
D、Because there are other better ways to preserve food.
答案C
解析 根据最后一段最后两句“Some people oppose the use of chemicals in food．They say that these chemicals may harm people if the chemicals can harm bacteria．”可知，一些人反对使用化学物质来保存食物是因为他们认为化学物质可以消灭细菌的话，对人体也会有害。故选C。
转载请注明原文地址:https://www.kaotiyun.com/show/craC777K
本试题收录于： 英语题库成考专升本分类
0

英语

成考专升本

相关试题推荐
随机试题
最新回复(0)