呼吸系统呼吸系统的两个主要用途是为身体输入氧气,排出二氧化碳。人类只有呼吸才能生存。没有氧,人的生命只能维持几分钟。但是很少人了解呼吸系统具有调节血液酸碱平衡的重要机能。呼吸系统由肺和一组输送空气和从体外将氧输入血流的分支组成。吸气时,人们将外部空气吸入口腔 Respiratory system The two main uses of the respiratory system are the introduction of oxygen into the body to expel the carbon dioxide. Humans only breathe to survive. Without oxygen, human life can only last for a few minutes. But few people understand that the respiratory system has an important function of regulating blood acid-base balance. The respiratory system consists of the lungs and a set of branches that deliver air and infuse oxygen into the bloodstream from outside the body. When inhaling, people inhale outside air into the mouth