Click on each organ to read about its function
The nose is the first part of the breathing system. It has two nostrils. Air passes through the nose from the atmosphere where it is cleansed, warmed and moistened. Air is cleaned by tiny hairs and mucus in the nose. The hairs trap dust and germs that may be in the air. After the air passes the nose, it goes to the trachea.
The trachea is also known as the windpipe. It is a pipe kept open by hard rings which are C-shaped. The trachea is the pipe that takes air from the nose to the lungs. It also has tiny hairs and some mucus that help trap dust and germs.
After the air passes through the trachea, it goes through one of two branches into either the left or right lung. Each branch is called a bronchus. Multiple of bronchus is bronchi. Each bronchus is divided into smaller branches called bronchioles. The bronchioles are found inside the lung.
We have two lungs. One on the right and one on the left. Lungs are located inside our chests. Bronchioles divide into fine tubes which open up to tiny air spaces called air sacs in the lungs. Each lung has millions of air sacs surrounded by tiny blood vessels. In the breathing system, exchange of air occurs in the air sacs. Oxygen is taken to the blood stream and carbon dioxide is taken out in the air sacs.
The diaphragm is a sheet of muscle that allows the lungs to expand and relax. It separates the chest from the abdomen. Expanding and relaxing of the diaphragm helps to breathe in and out.
When we breath in, the diaphragm moves downwards, expanding to allow the volume of the chest to increase. This is because the lungs expand to suck in air.
When we breath out, the diaphragm moves upwards. The volume of the chest decreases because the lungs contract to force air out of the lungs.
Video – song about the diaphragm: https://www.youtube.com/watch?v=kWHRz0P1L-g
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