The Respiratory System

• Alveoli


  Air sacs at the end of bronchioles where gas exchange takes place
• Alveoli


  • Grouped in clusters
  • A network of capillaries surrounds each alveolus
• Gas Exchange


  1. Oxygen diffuses into the blood

  2. Carbon dioxide in the blood diffuses into the alveolus
• Gas exchange takes place in the alveoli
• Oxygen


  For respiration
• Respiration (in biology)


  The release of energy from the breakdown of food in the presence of oxygen
• Respiration (at organism level)

  The process of gas exchange - the release of carbon dioxide and the uptake of oxygen that occurs between RBCs and alveoli
• Breathing


  The actual mechanical intake of air
• How the Lungs Work: Breathing

  1. Lungs are sealed in pleural membranes inside the chest cavity

  2. At the bottom of the cavity is a large, flat muscle known as the diaphragm

  3. During inhalation, the diaphragm contracts and the rib cage rises up

  4. This expands the volume of the chest cavity

  5. The chest cavity is sealed, so this creates a partial vacuum inside the cavity

  6. Atmospheric pressure fills the lungs as air rushes into the breathing passages
• How the Lungs Work: Exhalation

  1. Rib cage lowers

  2. Air Exhaled
• Order in which air travels until oxygen diffuses into your blood

  • Bronchioles
  • Nose
  • Pharynx
  • Bronchi
  • Alveoli
  • Larynx
• Asthma


  Condition in which breathing is impaired by constriction of bronchi and bronchioles, cough, and thick mucus secretions. The severity and incidence of asthma has risen dramatically in recent years, especially in children. May be fatal if not treated.
• Causes of Asthma


  Attacks may be precipitated by inhalation of allergens (e.g.: pollen, cats, and cockroach proteins), pollutants, infection, or emotional stress.
• Treatment of Asthma


  Alleviates symptoms (e.g.: immuno-suppressors, bronchodilators), but is not a cure.
• Bronchitis


  Inflammation of the mucous membranes of the bronchi. May present with cough, fever, chest or back pain, and fatigue.
• Causes of Bronchitis


  Associated with smoking, pollution, and bacterial or viral infections.
• Pneumonia


  Acute inflammation of the lungs. Symptoms include high fever, chills, headache, cough, and chest pain.
• Causes of Pneumonia


  Bacterial, fungal, or viral infections.
• Treatment of Pneumonia


  Antibiotics or other antimicrobials.
• Emphysema


  Permanent and irreversible destruction of alveolar walls, resulting in loss of lung elasticity and gas exchange surface. Symptoms include shortness of breath, difficulty exhaling, cough, weakness, anxiety, confusion, heart failure, lung edema (swelling), and respiratory failure.
• Causes of Emphysema


  Smoking, pollution, old age, and infections.
• Treatment of Emphysema


  Oxygen to help breathing. No cure.
• Lung Cancer


  Cancerous growth that invades and destroys lung tissue. Very high fatality rate. Symptoms include bloody sputum, persistent cough, difficulty breathing, chest pain, and repeated attacks of bronchitis or pneumonia.
• Causes of Lung Cancer

  Smoking (50% of all cases) and pollution (radon, asbestos). Smokers are 10 times more likely to develop lung cancer than nonsmokers.
• Treatment of Lung Cancer

  Surgery is most effective, but only 50% of all lung cancers are operable by time of detection. Other treatments include radiation and chemotherapy.
• Order in which air passes through structures from nose to lungs

  1. nose

  2. pharynx

  3. trachea

  4. bronchioles

  5. alveoli

  
• Alveoli


  Smallest respiratory passageways in the lungs where gas exchange takes place

  
• Palate


  Separates mouth from nose
• Alveoli


  Location where gas exchange takes place
• Pharynx


  Where both air and food pass through
• Exhalation


  The movement of air out of the lungs
• Diaphragm


  The main muscle involved in inhalation
• Process of inhalation


  1. The diaphragm contracts and flattens

  2. The muscles between the ribs contract to move the ribs up and out

  3. Air pressure in the chest cavity decreases

  4. Lungs expand

  5. Air is drawn into the lungs
• The purpose/function of the Respiratory System is

  
• The purposes of the pharynx are
• The purpose of the epiglottis is
• How the respiratory system is linked to the cardiovascular system