dioxide carbon involuntary breathing gas airways cell thorax energy nutrients cells exchange lungs oxygen exchang pulmonary blood waste carbon dioxide oxygen respiratory
The system is and automatic . Since our birth , you have been all the time thinking about it . Through respiration our body takes in from the air . Oxygen is transported in the to all the cells . In the , it is used to generate from . Finally , the is eliminated as . Respiration is the process of gas between and . The respiratory system consists of the and the . The lungs are organs located on each side of the and are responsible for