Respiratory system

• nose • lungs • windpipe • bronchi • ribcage • diaphragm

• air enters the system through the nose or the mouth - the nose contains nasal hair that traps dust and dirt from inhaled air

• it is a hollow tube that brings the air from the nose or the bronchi • the mucus in the windpipe prevents dirt and dust from entering the lungs. • cells in the windpipe secrets mucus • the hair like sturctures are found in the windpipe helps to sweep the mucus that contains dust and harmful substances • the mucus is later removed by spitting or swallowing it into the stomach

• the windpipe branches two tubes called the bronchi - the bronchi will carry air from the windpipe to the air sacs on the lungs

• it contains many air sacs surrounded by the blood vessels • oxygen moves from the lungs and into the blood stream ( inhaled air ) • carbon dioxide moves from the blood stream into the lungs ( exhaled air )

• it protects the lungs and heart - it also assists in the expansion and contraction of the lungs

• it is a muscular sheet below the ribcage • it contracts to allow air to enter the lungs • it relaxes to allow the air to leave the lungs

• the volume of the lungs increases • the ribcage moves upwards and outwards • the diaphragm contracts and moves downwards

• air is exhaled • the ribcage moves inwards and downwards • the diaphragm relaxes and moves upwards • the volume of the lungs decreases