手机APP下载

您现在的位置: 首页 > 英语听力 > 国外媒体资讯 > 听力文摘 > 正文

听力文摘第170期:鸟是如何呼吸的

来源:可可英语 编辑:shaun   可可英语APP下载 |  可可官方微信:ikekenet
  


扫描二维码进行跟读打分训练

How Birds Breathe

鸟是如何呼吸的
Don, flying is tougher than walking or running, right? So how come birds don’t get winded and run out of breath?
飞行比走路和跑步都要困难些,对吧?那为什么鸟类飞行的时候不会喘不过气来?
Actually, in terms of distance per unit energy, flying is pretty efficient. Plus birds have a super efficientrespiratory system. While a bird’s respiratory system takes up about one fifth of its body, its lungs are relatively rigid and small, and don’t fully deflate. Instead, birds have a complex network of air sacs that work like bellows to pump a constant stream of air through the lungs. What’s more, air only goes through the lungs in one direction, which means it has a higher oxygen content than the air in human lungs.
按照单位距离来看的话,飞行是非常顺利的。并且鸟类有一个特别高效的呼吸系统。当鸟呼吸系统占据它身体的五分之一时,它的肺比较僵硬,也比较小,不会完全紧缩。相反地,鸟类有一个复杂的肺泡结构,就像一个风箱把源源不断的空气打进肺里。更重要的是,空气在肺里只能流向一个方向,那就意味着它里面的氧气含量比人类肺里氧含量高。

When a bird inhales, the air goes into the rear air sacs, and when it exhales, that air moves forward to the lungs, where oxygen is exchanged for carbon dioxide waste. Then, when the bird inhales again, the air is pushed out of the lungs and into the front air sacs. When it exhales a second time, the air leaves the body.

鸟在吸气时,空气进入鸟肺泡的底部,而当呼气时,空气就向肺的前面移动,在那里氧气被交换成二氧化碳废气。然后,鸟再次吸气,气体就从肺中进入肺泡。当第二次呼气时,气体就从身体出来了。
So it takes two breaths to process a packet of air.
所以鸟类需要呼吸两次才能处理气体了。
Yep, Plus the air sacs mean that birds weigh less than you’d expect, which makes flying less costly in terms of energy. But scientists still don’t fully understand how birds breathe. Birds fly over Mount Everest at altitudes where the air is so thin humans can’t function, and no one knows how they do it.
是的。加上肺泡的话就说明鸟比我们想象的要轻,那样飞行就不会那么耗能量。但是科学家们现在也不完全明白鸟类是如何呼吸的。鸟可以在珠穆朗玛峰上空飞行,但山上空气太稀薄人类无法呼吸,没有人知道它们是怎么做到的。

重点单词   查看全部解释    
function ['fʌŋkʃən]

想一想再看

n. 功能,函数,职务,重大聚会
vi. 运行

 
complex ['kɔmpleks]

想一想再看

adj. 复杂的,复合的,合成的
n. 复合体

联想记忆
understand [.ʌndə'stænd]

想一想再看

vt. 理解,懂,听说,获悉,将 ... 理解为,认为<

 
network ['netwə:k]

想一想再看

n. 网络,网状物,网状系统
vt. (

 
rigid ['ridʒid]

想一想再看

adj. 僵硬的,刻板的,严格的

 
pump [pʌmp]

想一想再看

n. 泵,抽水机,打气筒,抽水,打气
v. 打

 
stream [stri:m]

想一想再看

n. (人,车,气)流,水流,组
v. 流动,

 
respiratory [ri'spirətəri]

想一想再看

adj. 呼吸的,与呼吸有关的

 
costly ['kɔstli]

想一想再看

adj. 昂贵的,代价高的

联想记忆
constant ['kɔnstənt]

想一想再看

adj. 经常的,不变的
n. 常数,恒量

联想记忆

发布评论我来说2句

    最新文章

    可可英语官方微信(微信号:ikekenet)

    每天向大家推送短小精悍的英语学习资料.

    添加方式1.扫描上方可可官方微信二维码。
    添加方式2.搜索微信号ikekenet添加即可。