The passages through which air passes on its way to the lungs make up the respiratory tract .

The components above the lungs are referred to as the upper respiratory tract . These are:

• the nose (including the nasal cavities into which air enters from the nostrils),
• the pharynx (the medical term for the throat),
• the larynx - which also contains the vocal cords (voicebox) used in voice production - and
• the trachea.

When we need to breathe more heavily, for example during exercise, we breathe through the mouth as well as the nose - but the mouth is not normally regarded as being part of the respiratory system.

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