Respiratory System Breath in oxygen and supply to the blood Expel carbon dioxide (waste product of cellular respiration) into the atmosphere Filter, moisten, warm the air during inhalation/exhalation

Upper Respiratory Tract Nasal Cavity – Hollow space behind the nose – Lined with mucus to trap foreign particles Pharynx (Throat) – Air and food pass through – Conducts air towards the larynx and food towards the esophagus Epiglottis – Flap of tissue that covers the entrance to larynx Larynx (voice box) – Contains two bands of tissue called the vocal cords Trachea (windpipe) – Made of cartilaginous rings – Lined with cilia, secrete mucus

Lower Respiratory Tract Lungs – Right/Left – Right has three lobes – Left has two lobes Bronchi – Two tubes that branch from the trachea – Lead into the lungs Bronchioles – Smaller tubes branch from bronchi – Connect to the alveoli Alveoli – Air sacs within the lungs where gas exchange occurs

Gas Exchange Difference in Concentration Gradient – Inhaled air has greater concentration of O₂ – Deoxygenated blood in body has greater concentration of CO₂ Diffusion of O₂/CO₂ across membrane happens simultaneously Occurs in Alveoli and somatic cells Surfactant – Lowers surface tension in alveoli

Breathing Involves changes of pressure in lungs Inhalation – Diaphragm and rib muscles contract – Chest cavity expands – Air pressure decreases – Lungs expand Exhalation – Diaphragm and rib muscles relax – Chest cavity contracts – Air pressure increases – Lungs contract

Dyspnea Shortness of breath (SOB) Causes (85% of cases) – Asthma, pneumonia, cardiac ischemia, interstitial lung disease, congestive heart failure, chronic obstructive pulmonary disease

Asthma Chronic inflammatory disease of the airways Symptoms – Wheezing, coughing, chest tightness, shortness of breath Causes – Genetics, pollution, smoking, allergies Treatment (Albuterol) – Puffer, pill, syrup

Chronic Obstructive Pulmonary Disease (COPD) Persistently poor airflow as a result of breakdown of lung tissue Emphysema – Damage to alveoli Chronic Bronchitis – Inflammation of bronchi, airways become narrow and clogged with mucus Causes – Smoking, occupation, air pollution Treatment – No cure – Steroids, anti-inflammatory drugs, oxygen therapy, quit smoking

Diagnostic Test For Respiratory Health Chest X-ray – Uses x-ray radiation to form images of bones, tumors, TB inside the chest – Lung cancer, pneumonia, TB MRI – Uses magnetic fields to form cross-section images of bones and soft tissues – Blood clot in lungs, lung cancer, cystic fibrosis Sputum Test – Used to test mucus from the lungs and bronchi for bacteria and other microbes – TB, pneumonia

Diagnostic Test For Respiratory Health Arterial Blood Gas Test – Test blood sample for oxygen and carbon dioxide concentrations – Asthma, cystic fibrosis Stethoscope – Amplify and listen to lung sounds while person breathes Pulmonary function test – Measures amount of air moving in and out of lungs during different types of breathing – Asthma, bronchitis, emphysema