Respiratory System Disorders

Diseases and Infections interfere in two main ways: 1)Restrict the flow of air into and out of the lungs 2)Impairs the gas exchange due to a reduced surface area for diffusion

Pneumonia Alveoli become inflamed & fill with thick fluid Inflammation of the lining of the bronchi Decreased airway & impaired gas exchange

2 types of Pneumonia See fig page 456 Bronchial pneumonia affects patches in both lungs Lobular involves a single lobe and most often caused by bacteria

Causes of Pneumonia Bacterial infection / viral infection Can spread to other organs Treated with anti-virals or antibiotics

Bronchitis -Tissue of the bronchi become red, inflamed, and filled with mucus -Restricts air flow

Causes of bronchitis -Acute bronchitis (short-term) = bacteria -Chronic bronchitis (long-term) = regular exposure to dust, chemicals, cigarette smoke * Cilia lining is gradually destroyed

Asthma Inflammation of the bronchi and bronchioles Air flow is reduced Muscles around the airway contract during an asthma attack

Causes of Asthma Inhaled irritants such as pollen, dust and smoke Asthma medications act by relaxing the bronchiole muscles by reducing inflammation

Emphysema Tissue that supports the structure of the lung is destroyed The elasticity of the alveoli is lost

Reduces the respiratory surface for gas exchange Exhalation is difficult – trapping air in the lungs Most common cause is SMOKING

Cystic Fibrosis

Effects of CF Cells lining the airways release thick, sticky mucus Clogs the lungs Mucus traps disease causing agents