The Respiratory System • The system that provides oxygen for the body and allows carbon dioxide to leave the body • This system works in close association with the circulatory system
Label the diagram: Nasal cavity Mouth Trachea Bronchi Bronchiole Lung Ciliated epithelial cells Alveoli
Structure of the Respiratory System • Air enters through mouth and nasal cavity • Travels through trachea • Trachea separates into to bronchi (singular – bronchus) • Bronchi split into bronchioles • Alveoli are small sacs at the ends of the bronchioles • These are the sites of gas exchange with the circulatory system
Structure of the Respiratory System • Many of the epithelial cells that line the respiratory pathway are goblet cells (produce mucus). In addition, these cells also contain cilia • Cilia help move mucus and filter out and materials that may enter the system (bacteria, dust, etc.) • The trachea is supported by rings of cartilage • This keeps the trachea open at all times, while still allowing flexibility • (your ears are also made of cartilage)
Why doesn’t food get in my trachea? • Because of the EPIGLOTTIS • When you swallow, the epiglottis (a small flap) covers the opening of the trachea
Gas Exchange • Oxygen and carbon dioxide need to be exchanged. • This occurs between the alveoli of the respiratory system and the capillaries of the circulatory system • An alveolus is a sac of air at the end of the respiratory system • Each alveolus is surrounded by a capillary network
Gas Exchange • Blood coming from the heart is deoxygenated (carrying CO2) • The CO2 diffuses from the capillary to the alveolus • O2 diffuses from the alveolus to the capillary • The CO2 is EXHALED as waste • The O2 is then brought back to the heart, where it is pumped to all cells in the body.
Disorders and Diseases • Tuberculosis • Bronchitis • Bronchial Asthma • Carbon Monoxide Poisoning • Lung Cancer • Common Cold