What are the three main functions of the upper airway?

Answer 1

The upper respiratory tract consists of the nose, the pharynx and the larynx.

The nose has several functions;

- it warms, cleanses and humidifies inhaled air

- it detects odors in the airstream

- it acts as a resonating chamber that amplifies the voice

The Pharynx is a muscular funnel (about 13cm long) that is divided into 3 parts; the nasopharynx, the oropharynx and the laryngopharynx. Air passing through the nasopharynx has to turn 90degrees downwards and any large particles (more than 10 micrometers) can't make the turn and crash into the wall of the nasopharynx and stick to the mucosa near the tonsil (well positioned to respond to airborne pathogens). The oropharynx is the area near the root of the tongue and ends just before the epiglottis (the flap that prevents food going into the lungs when swallowing). The laryngopharynx starts at the tip of the epiglottis and ends where the oesophagus begins (the tube that goes to the stomach). The nasopharynx passes only air, whereas the oropharynx and laryngopharnx pass air, food and drink.

The larynx, also called the voice box, has two main functions. The primary one is to keep food and drink out of the airway and it has evolved the ability to produce sound so allows humans to talk. During the swallowoing process, the larynx is pulled upward toward the epiglottis while the tongue pushes the epiglottis downward to meet it, the epiglottis then closes the airway and directs food and drink down the oesophagus behind it.

To summarise, the main function of the upper respiratory tract is to allow the passage of air through to the lower respiratory tract whilst preventing any food and drink obstructing the airway.The air is also warmed, cleansed and humidified, smells can be detected, large airborne particles are prevented from getting into the lungs and humans are able to produce speech.

Answer 2

The Upper Respiratory tract is responsible for warming, moistening & filtering inhaled air.

It is also responsible for olfaction (smelling)

Answer 3

To bring air jnto the lower airways, and to purify, humidify, and warm air while it's getting there.