Function: Gas Exchange Respiratory System Function: Gas Exchange Bringing oxygen into the body Getting rid of carbon dioxide

Nostrils & Pharynx Air enters nose or mouth Nostrils trap and filter out dust and foreign particles using tiny hairs and mucus Air is warmed up and moistened Air passes through pharynx

Trachea Air moves into trachea Also known as the windpipe, contains: A flap-like structure called the epiglottis When swallowing food, it prevents it from passing into trachea The larynx (also known as the voice box)

Bronchi Singular form: Bronchus Two air passages that move inhaled air from the trachea to the right or left lung Bronchi are divided into bronchioles. Cilia (tiny hairs) line the inside of the trachea, bronchi and bronchioles and are coated with mucus = prevents bacteria, dust and pollen from entering further down the lungs. Cilia sweeps it upwards to mouth (cough reflex).

Lungs Air moves from bronchi into: Bronchioles – divided from the bronchus that become smaller until they reach tiny air sacs called alveoli Alveoli – tiny air sacs where gas exchange occurs Capillaries (tiny blood vessels) surround alveoli: remove CO2 from blood and absorb O2 Red blood cells pick up O2 to send it to rest of body