Be able to able to label parts of the respiratory system Be able to able to label parts of the respiratory system. The Respiratory System

What is the main job of the respiratory system? Functions: Works closely with circulatory system, exchanging gases between air and blood: Takes up oxygen from air and supplies it to blood (for cellular respiration). Removal and disposal of carbon dioxide from blood (waste product from cellular respiration). Regulates blood pH. Regulates blood oxygen and carbon dioxide levels.

Components of the Upper Respiratory Tract Figure 10.2

Upper Respiratory Tract Functions Passageway for respiration Receptors for smell Filters incoming air to filter larger foreign material Moistens and warms incoming air Resonating chambers for voice

Components of the Lower Respiratory Tract Figure 10.3

Explain how the respiratory system is protected from particles? Small hairs in your nose, called cilia, help filter out large particles. Cilia are also found along your air passages and move in a sweeping motion to keep the air passages clean. But if harmful substances, such as cigarette smoke, are inhaled, the cilia stop functioning properly, causing health problems like bronchitis. Mucus produced by cells in the trachea and bronchial tubes keeps air passages moist and aids in stopping dust, bacteria and viruses, allergy-causing substances, and other substances from entering the lungs. Impurities that do reach the deeper parts of the lungs can be moved up via mucous and coughed out or swallowed.

Lower Respiratory Tract Functions: Larynx: maintains an open airway, routes food and air appropriately, assists in sound production Trachea: transports air to and from lungs Bronchi: branch into lungs Lungs: transport air to alveoli for gas exchange

Define: trachea, bronchi, bronchioles, and alveoli Functions: Larynx: maintains an open airway, routes food and air appropriately, assists in sound production Trachea: transports air to and from lungs Bronchi: branch into lungs Lungs: transport air to alveoli for gas exchange

Why must the alveolar membranes be thin Why must the alveolar membranes be thin? Gas Exchange Between the Blood and Alveoli Figure 10.8A

What is the diaphragm and what does it do What is the diaphragm and what does it do? Describe what happens during inhalation and exhalation. Respiratory Cycle Figure 10.9

Breathing Ventilates the Lungs Breathing: Alternation of inhalation and exhalation. Supplies our lungs with oxygen rich air, and expels excess carbon dioxide. Inhalation: Diaphragm contracts, moving downward and causing rib cage, chest cavity, and lungs to expand. Air rushes in, due to decrease in internal lung pressure as lungs expand. Exhalation: Diaphragm relaxes, moving upwards and causing rib cage, chest cavity, and lungs to contract. Air rushes out, due to the increase in internal lung pressure as lungs contract. Breathing is controlled by centers in the nervous system to keep up with body’s demands.

Regulation of Breathing What does the brain detect to determine rate of breathing? Regulation of Breathing Figure 10.13

Regulation of Breathing: Nervous System Involvement Carotid and aortic bodies: sensitive to carbon dioxide, pH, and oxygen levels Conscious control: resides in higher brain centers; ability to modify breath is limited