Respiration & breathing

你需要知道的

• Breathing (the respiratory system) and cellular respiration are different: breathing brings oxygen in and removes carbon dioxide, while respiration happens in cells.
• Cells need oxygen to release energy from glucose, and carbon dioxide is the waste gas produced.
• Air passes through the nose, trachea, bronchi and bronchioles to the alveoli, where gas exchange happens across thin walls with a large surface area and many capillaries.
• The rib cage protects the lungs, and the intercostal muscles and diaphragm change the size of the chest during breathing.
• Rising carbon dioxide in the blood is detected by the brain, which speeds up breathing during exercise.

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