Respiratory System

Do Now: 1. Cellular Respiration happens in our cells. How does the respiratory system make this possible? 2. What is the main job of the respiratory system? 3. What muscle contracts and expands to allow us to inhale and exhale?

Respiration: the process by which oxygen (O2) is brought into the body and carbon dioxide (CO2) is removed

Nasal Passage Nose (Nostrils) Bronchiole Mouth (Oral Cavity) Epiglottis Artery Larynx (Voicebox) Vein Trachea Bronchi Lung Alveoli Capillaries Alveoli Diaphragm

Inhalation & Exhalation Air enters the respiratory system when you inhale through your nose or mouth. Inhalation occurs when the diaphragm muscle moves down, forcing air into your lungs. Exhalation occurs when the diaphragm muscle moves up, forcing air out of your lungs.

Air Pathway After inhalation, the air must pass through a series of tubes before it can reach your lungs. It starts off in one tube called the trachea. The trachea branches off into two bronchi. Each bronchi then branches off into many bronchioles. Each bronchiole ends with multiple alveoli.

Gas Exchange The exchange of gases takes place across the thin, moist membrane of the alveoli. In order for this exchange to take place, the alveoli are surrounded by capillaries. Oxygen (O2) diffuses from the alveoli into the blood and carbon dioxide (CO2) diffuses out of the blood into the alveoli.

The Alveoli

Diseases of the Respiratory System Asthma/Allergies: The lining in your airways becomes sore and swollen During an attack they narrow, causing wheezing, coughing, and trouble breathing

Diseases of the Respiratory System Lung Cancer: Can start anywhere in the lungs and affect any part of the respiratory system Caused by: smoking exposure to: secondhand smoke, asbestos, radon