跑步时不宜只用鼻呼吸跑步时，人体对氧的需要量增加。如果跑步_爱下问搜题

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问题问答题

跑步时不宜只用鼻呼吸

跑步时，人体对氧的需要量增加。如果跑步时只用鼻呼吸，将满足不了人体对氧的需要，此时势必迫使呼吸肌加强运动，加快呼吸频率，以提高肺的通气量，满足人体对氧的需要。其结果是呼吸肌会较快疲劳，反而影响氧的供应。因此，跑步时，应适当张口协助鼻进行呼吸。据研究，兼用口、鼻呼吸，肺的通气量可由只用鼻呼吸时的80升/分钟增加至173升/分钟，并且因呼吸频率不过快，而延迟呼吸肌疲劳的产生。通过口腔，还可以辅助散发运动中产生的热量。但是，在严冬进行跑步时，张口不易过大，这样可使吸入的冷空气经过口腔得到预热，从而减少对呼吸道和肺的不良刺激。

思考：口是消化器官，通过口的气体为什么也能进入肺呢？由口吃进的食物会不会也进入气管或肺呢？

答案

咽是呼吸器官也是消化器官，上连口腔、鼻腔，下通食道和气管；当人吃饭时说笑，会厌软骨来不及盖住喉口，食物就可能误入气管，由气管内纤毛摆动再由咳嗽咳出，正常情况下，食物不会进入肺。

完形填空

My oldest child, Emma, just returned to campus after a long holiday break to finish up her last period of ______. These days, friends and family have begun _____ me with one question: What is she going to do after _____?
The job market is, after all, awfully ______. Just this month the Federal Reserve Bank _____ a study showing that “recent graduates are ______ working in low-paid jobs or working part-time.” The ______ spot, according to the study, is for students who majored(主修) in STEM— science, technology, engineering and ______— areas in which recent graduates “have______ to do relatively well”.
But Emma is a student of the humanities(人文) at a small college. She’s an American Studies major with a（an） ______ on the politics and culture of food. For quite a while, I think her field of study is so fashionable right now that I’m not the least bit ______ she will find a good job. Yet the more I’ve thought about it, the more I’ve decided to be honest. “I’m not sure what Emma is going to do,” I now say. “But she’s gotten a great education and has really found her ______. — and I know those things will serve her well over the _____ of her life.”
Nowadays, more and more universities and colleges are being ______ by the salaries of their recent graduates. In this climate, ______ your kid to study the humanities, seems, at best, unwise or, at worst, unconcerned with ______ a living. But a college is not a vocational(职业) school. And promoting STEM subjects should not be society’s only answer to helping the next generation grow in a competitive world.
From the beginning, we never urged Emma to ______ a college or a major with an eye on its expected return on money, ______ more and more families are doing. To Emma, what really ______ will be something that we may not be able to measure for quite a long time: Emma’s ______ to the world and how happy she is in it.

A．surprisingly

D．increasingly

A．mathematics

A．discouraging

D．encouraging

A．contribution

C．desperation

单项选择题

罗马法规定，作为权利义务主体的自然人必须具有人格，即享有权利和承担义务的资格。人格由自由权、市民权和家庭权三种身份权构成。罗马法规定，只有同时具备上述三种身份权的人，才能在法律上享有完全的权利能力，才属于具备完整人格的人。罗马法的此项规定（）

A.为资产阶级战胜封建势力提供了理论武器

B.为资本主义经济的发展提供了法律形式

C.为资产阶级的民权理论提供了思想渊源

D.为资产阶级国家的法律体系树立了楷模