People can actually survive a small period of time without food or water but what is the one thing we absolutely need to stay alive? It is oxygen (O2) which we get when we breathe. This is exactly what makes the lungs so important – they are the organ that brings oxygen into our body.
We have two lungs – left and right on each side of our chest. Together with the heart they are protected by the ribcage. Each lung is made up by lobes – the right one 3; the left one has only 2 because it is smaller – it needs to make some room for the heart. The lungs are just a small part of our respiratory system. It very much resembles a tree – with a trunk, branches and various tinier twigs. Let’s see precisely how it works. When we breathe, we inhale air through the nose or mouth. Then the air goes down the trachea, which is also called a windpipe. From there it enters the bronchi – two breathing tubes, left and right for each lung. The bronchi divide into the smaller twigs of this amazing ‘breathing tree’ – the bronchioles. At the end of each bronchiole the alveoli are found. Their names mean ‘a bunch of grapes’ and depict very accurately what they look like – microscopic bags full of air. They are covered in very small blood vessels, called capillaries whose job is to take the oxygen to the heart. From there it can be distributed by the blood throughout the whole body. When we exhale, carbon dioxide is carried back from the cells to the lungs so it can be released in the air. Carbon dioxide (CO2) is the waste gas produced during the process of breathing.
A lung is a hard-working organ. When resting, an adult breathes in 12-20 times a minute, much more frequently when we exericise. Unfortunately, there are not only a couple of diseases that can disturb the work of the lungs like asthma (the airways narrow so a person has difficulties breathing), allergies or lung infections (caused by viruses or bacteria). One of the biggest culprit for the lungs is smoking. The cigarette smoke causes the alveoli to shrink so the volume of the lungs decreases. Once an alveolus has died, it does not grow back which means that the damage to the lungs is permanent and irreversible!!
blood vessel – a small tube in which the blood circulates in the body (an artery, vein, or capillary)