首页
登录
职称英语
Imagine an animal that becomes frozen in cold weather. Then, when it gets wa
Imagine an animal that becomes frozen in cold weather. Then, when it gets wa
游客
2024-02-06
57
管理
问题
Imagine an animal that becomes frozen in cold weather. Then, when it gets warmer, the animal simply unfreezes and goes back to its normal life. Although this may sound like something from a science-fiction movie, it is exactly what happens to the wood frog over winter and spring. When winter begins, the frog, which is found throughout much of Canada, buries itself in leaves and dirt. As the ground begins to freeze, so does the frog’ s body.
Normally, if a living creature is frozen, the cells inside its body are destroyed, leading to death. How, then, does the wood frog survive? The secret lies in the fact that although the water between the cells in the frog’ s body becomes frozen, the water inside the cells does not freeze. Before the winter begins, the frog stores starch in its body. As the weather gets colder, the drop in temperature causes the frog’ s body to change this starch into glucose. This glucose, in turn, lowers the temperature at which the liquid inside the frog’s cells freezes. As a result, the cells do not freeze even at very low temperatures, allowing the frog to stay alive. Some wood frogs stay in this frozen state— with their hearts stopped completely—for months without harm.
Now researchers are hoping to adapt the wood frog’ s secret to help them preserve human organs for transplants. Currently, after organs are removed from a donor’ s body, they are packed in a special liquid and kept very cold. However, they cannot be frozen because the ice would damage the cells in the organs. For this reason, the organs must be used quickly. If doctors had a way to preserve organs longer, they would have more time to find the best matches among people waiting for organ transplants.
There is still a lot about the wood frog that scientists do not understand. They still have to work out, for example, exactly how the frog is able to unfreeze itself and what actually restarts the frog’s heart when the weather becomes warmer. What is clear, however, is that lessons learned by studying this tiny creature could be of great benefit to humans in the near future. [br] Which is one thing that scientists would like to find out about the wood frog?
选项
A、Whether it becomes frozen in the spring.
B、How its heart starts again when it unfreezes.
C、Which parts of its body freeze in cold weather.
D、Why it takes so long to unfreeze at the end of winter.
答案
B
解析
细节题。作者在最后一段指出…work out…how the frog is able to unfreezeitself and what actually restarts the frog’s heart…,由此可知,答案为B。
转载请注明原文地址:https://tihaiku.com/zcyy/3426642.html
相关试题推荐
Someanimalsarewidelyusedinexperiments______(尽管有些人对此表示反对).eventhoughsome
ImaginebeingaslaveinancientRome.Nowrememberbeingone.Thesecondta
ImaginebeingaslaveinancientRome.Nowrememberbeingone.Thesecondta
ImaginebeingaslaveinancientRome.Nowrememberbeingone.Thesecondta
[originaltext]W:Wow!(19)Therearesomanychoices!ThereareanimalshereI’ve
[originaltext]W:Wow!(19)Therearesomanychoices!ThereareanimalshereI’ve
It’swellknownthatbiganimals,likepolarbears,aresensitivetoclimate
It’swellknownthatbiganimals,likepolarbears,aresensitivetoclimate
It’swellknownthatbiganimals,likepolarbears,aresensitivetoclimate
It’swellknownthatbiganimals,likepolarbears,aresensitivetoclimate
随机试题
TheproportionofmanufacturingcompaniesinAlamedathatusemicroelectronicsi
PASSAGEONE[br]Whatdoes"itshiddenimport"inthelastsentencemean?Thesca
Thesubjectoftoday’slectureiscultureshock:grouppressureinaction.C
运料斜道的宽度和坡度的规定是()。A.不宜小于0.8m和宜采用1:6 B.
因二氧化碳等气体造成的温室效应会使地球表面温度升高而引起自然灾害。二氧化碳等气体
油浸电容型套管事故抢修安装前,如有水平运输、存放情况,安装就位后,带电前必须进行
两个卡诺热机的循环曲线如图所示,一个工作在温度为T1与T3的两个热源之间,另一个
慢性胰腺炎传统的“三联症”是指A.上腹痛、胰腺钙化、脂肪泻 B.胰腺钙化、脂肪
据报载,著名物理学家、英国剑桥大学教授斯蒂芬·霍金宣布他已放弃对“万有理论”(T
(2019年真题)甲公司为居民企业,登记注册地在W市,企业所得税按季预缴。主要
最新回复
(
0
)