HOW DO WE BREATHE?

All animal life must take oxygen in, in some form or the other, otherwise known as breathing. Human beings do this by taking air into the lungs.

Breathing is something, which we don’t really even think about, but breathing can actually involve quite a process.

Breathing is done by air passing through the body via a series of tubes know as ‘the upper respiratory tract’. Starting from the nose, particles which might be harmful to the lungs are trapped or strained, while the nose at the same time warms the air.

From the nose, the air will pass through the ‘pharynx’, or throat. The air will then pass two smaller tubes known as ‘bronchi’. One of these ‘bronchi’ will from there enter the lungs. These lungs are soft, large organs, having a thing covering  called ‘the pleura.’

The tissue of the lung could be thought of as being like a fine sponge. In the lung/ lungs there are small spaces (air sacs). This is where the air will leave the ‘bronchi’, the gases that the body needs will from here be extracted and the unwanted gasses are discarded and forced out of the body. The air spaces are what are known as ‘alveoli’.

The air that our body takes in contains oxygen, nitrogen, carbon dioxide as well as water vapour. All of these gases are also present in the blood in different amounts. When a fresh breath of air is drawn more oxygen is contained in the ‘alveoli’ than in the blood stream. This is how the oxygen is then able to pass through the thin walls of the blood vessels (capillaries) and into the blood stream. The Carbon dioxide will leave the blood stream into the air sacs from where it is exhaled.