Respiratory system structure

It is here that the air is warmed, filtered (by tiny hairs), and moistened.  From here, the air passes through the pharynx.​ ​

• Nose

• Mouth

• Throat

• Pharynx

There are millions of these in each lung and it is here that gaseous exchange takes place.  They have large surface areas, thin walls and are surrounded by a network of pulmonary capillaries.​ ​

• Nose

• Alveoli

• Pharynx

• Larynx

Lies behind the nose and mouth and both cavities open into it.  Both food and air pass through here, the food is then directed to the oesophagus. ​

• Nose

• Alveoli

• Pharynx

• Larynx

Here, the epiglottis prevents food from entering the windpipe (trachea), into the lungs.​ ​

• Nose

• Alveoli

• Pharynx

• Larynx

The trachea divides into two of these, one leading to each lung. ​

• Larynx

• Bronchi

• Bronchioles

• Alveoli

The bronchial tubes further divide into smaller tubes before terminating in clusters of air sacs known as alveoli. ​ ​

• Larynx

• Bronchi

• Bronchioles

• Alveoli

Approximately 10-12cm long and is kept open by a series of rings of cartilage.  It contains cells which remove foreign particles from the air. ​ ​

• Bronchioles

• Bronchi

• Alveoli

• Trachea