Your nose and throat also have other functions, such as carrying air to the lungs.

Connections between your nose, throat and ears mean that a problem in one area can spread to the others.

How your nose works

As you breathe in, your nose:

• cleans the air of foreign particles
• warms and humidifies the air before it reaches your lungs.

This is helped by the thin moist lining of your nasal passages and throat, called mucosa.

The cells in the lining of your nose also sense aromas and send messages to your brain. This gives you your sense of smell.

How your throat works

Your throat, or pharynx, sits behind your nose and your mouth and is connected to both of them.

The pharynx is a muscular tube that carries both food, drinks and air. As it goes down, it splits in 2 — the oesophagus and the larynx.

The oesophagus is the tube that leads from your throat to your stomach. It carries food and drink.

The larynx carries air. The larynx also contains your vocal cords which produce sound, allowing you to speak. Air passes through the larynx into the trachea and then into the lungs.

Obviously, you need a way of keeping air and food apart. This is done by the epiglottis, which is a small flap of cartilage in the back of your throat. It closes over the larynx when you swallow so that you don’t breathe in food or water.

Problems in your nose and throat

The connections between your nose and throat, sinuses and ears, mean that fluids can move from one area to another. This is how a cold becomes a sinus, throat or ear infection.

Visit your doctor if your symptoms continue for more than a week, or you have other symptoms such as a fever or rash.