The Respiratory System
Why Breathe?
The Respiratory System Is responsible for providing oxygen to the cells of the body and for removing the carbon dioxide that has been produced as your body uses energy for growth, repair and movement
Diagram nose Pharynx (throat) Cilia on epithelial tissue (cleans air) Trachea (supported by cartilage) bronchi capillaries lung alveoli bronchiole
Nose and Mouth
Pharynx (Throat)
Larynx (voice box)
Trachea (windpipe)
Trachea – With Epithelial cells Epithelial cells produce mucus and have cilia cilia moves mucus and filters out any foreign material that enters the system) Goblet cells secrete mucus
Lungs
Bronchi &Bronchioles The Bronchi deliver air to the lungs
Alveoli (& Capillaries)
Gas Exchange Each Bronchiole branch ends in tiny air sacs called alveoli surrounded by capillaries allowing for oxygen to diffuse into the blood and carbon dioxide to diffuse into the alveolus. The concentration of oxygen in the blood that flows through the lungs is always less than the concentration of oxygen in the air in the alveoli. Why? Oxygen will diffuse from an area of high concentration (in the alveoli) to an area on low concentration (in the blood).
Breathing Moving air into (inhalation) and out of (exhalation) the lungs Muscles between the ribs help expand and contract the rib cage The diaphragm (large sheet of muscle below the lungs) also expands and contracts to increase/decrease lung volume. As the lung volume changes the pressure inside the lungs changes allowing oxygen to move into the alveoli.
Inhalation Volume of the lungs increases Rib cage expands Diaphragm flattens In the alveoli there is now a higher level of oxygen compared to that of the blood therefore allowing oxygen to diffuse into of the capillaries which is lower in oxygen.
Exhalation The volume of the lungs decreases The muscles relax and the diaphragm becomes dome shaped decreasing the volume of the lungs therefore pushing air out.
Can we control breathing? Yes but eventually Involuntary The brain detects the level of oxygen in the blood As the carbon dioxide levels increase the brain sends signals to the diaphragm, the muscles between the ribs, and the heart causing the breath rate to increase and the heart to beat faster (a double effect to decrease carbon dioxide concentration in the blood and increase oxygen
Remember the respiratory system relies on the circulatory system to deliver oxygen to the cells and remove carbon dioxide Lungs (air containing oxygen, carbon dioxide, and other gases Circulatory System Tissues (cells requiring oxygen and producing carbon dioxide)
Videos
Homework Take notes on diseases of the respiratory system p. 94 Answer questions #1,2,3,4,6