2. 职业资格
  3. It’s one of our common beliefs that mice are afraid of cats. Scientists have long known that even if a mouse has never seen a ca

It’s one of our common beliefs that mice are afraid of cats. Scientists have long known that even if a mouse has never seen a ca

admin2022-12-26  43
问题     It’s one of our common beliefs that mice are afraid of cats. Scientists have long known that even if a mouse has never seen a cat before, it is still able to detect chemical signals released from the cat and run away in fear. This has always been thought to be something that is hard-wired into a mouse’s brain.
    But now Wendy Ingram, a graduate student at the University of California, Berkeley, has challenged this common sense. She has found a way to "cure" mice of their inborn fear of cats by infecting them with a parasite, reported the science journal Nature.
    The parasite, called Toxoplasma gondii, might sound unfamiliar to you, but the shocking fact is that up to one-third of people around the world are infected by it. This parasite can cause different diseases among humans, especially pregnant women—it is linked to blindness and the death of unborn babies.
    However, the parasite’s effects on mice are unique. Ingram and her team measured how mice reacted to a cat’s urine before and after it was infected by the parasite. They noted that normal mice stayed far away from the urine while mice that were infected with the parasite walked freely around the test area.
    But that’s not all. The parasite was found to be more powerful than originally thought—even after researchers cured the mice of the infection. They no longer reacted with fear to a cat’s smell, which could indicate that the infection has caused a permanent change in mice’s brains.
    Why does a parasite change a mouse’s brain instead of making it sick like it does to humans? The answer lies in evolution.
    "It’s exciting and scary to know how a parasite can manipulate a mouse’s brain this way," Ingram said. But she also finds it inspiring. "Typically if you have a bacterial infection, you go to a doctor and take antibiotics and the infection is cleared and you expect all the symptoms to also go away." She said, but this study has proven that wrong. "This may have huge implications for infectious disease medicine."
The experiment found that mice infected with Toxoplasma gondii
选项 A、stayed far away from a cat’s urine
B、moved around the area freely and fearlessly
C、became more sensitive to a cat’s smell
D、were more afraid of cats
答案B
解析 细节题。根据第四段中的“They noted that normal mice stayed far away from the urine while mice that were infected with the parasite walked freely around the test area”可知，受到弓形虫感染的老鼠能够自由随意地在测试区域周围走动。故本题选B。
转载请注明原文地址:https://kaotiyun.com/show/RsVD777K
本试题收录于： 英语学科知识与教学能力题库教师资格分类
0

英语学科知识与教学能力

教师资格

相关试题推荐
随机试题
最新回复(0)