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Respiratory Volumes and Capacities

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Respiratory Volumes and Capacities Spirometry measures various lung volumes and capacities to assess respiratory function. Lung Volumes (Four Primary Volumes) 1. Tidal Volume (TV) Volume of air inhaled or exhaled during normal, quiet breathing Approximately 500 mL 2. Inspiratory Reserve Volume (IRV) Additional volume of air that can be inhaled after a normal tidal inspiration Approximately 3,100 mL in males, 1,900 mL in females 3. Expiratory Reserve Volume (ERV) Additional volume of air that can be exhaled after a normal tidal expiration Approximately 1,200 mL in males, 700 mL in females 4. Residual Volume (RV) Volume of air remaining in the lungs after maximal expiration Approximately 1,200 mL Cannot be measured by spirometry (requires specialized techniques) Prevents alveolar collapse Lung Capacities (Combinations of Two or More Volumes) 1. Inspiratory Capacity (IC) Maximum ...

Regulation and Mechanism of Respiration

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  Regulation and Mechanism of Respiration Respiration is a tightly controlled process that ensures adequate oxygen (O₂) delivery and carbon dioxide (CO₂) removal under resting and stressed conditions (exercise, disease, drug effects).  For pharmacy students, understanding how breathing is generated, regulated, and modified is essential for interpreting respiratory diseases and the actions/side effects of many drugs (opioids, sedatives, bronchodilators, etc.). 1. Levels of Respiration In physiology, “respiration” includes three related processes: Pulmonary ventilation – Movement of air into and out of the lungs (breathing). External respiration – Gas exchange between air in alveoli and blood in pulmonary capillaries. Internal respiration – Gas exchange between systemic capillaries and tissue cells. 2. Mechanics (Mechanism) of Pulmonary Ventilation (Breathing) Pulmonary ventilation consists of two phases: inspiration (inhalation) and expiration (exhalation) . ...

Anatomy of Respiratory Organs and Their Functions

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Anatomy of Respiratory Organs and Their Functions Introduction The respiratory system is a vital organ system responsible for gas exchange—taking in oxygen and expelling carbon dioxide. For pharmacy students, a thorough understanding of respiratory anatomy and physiology is crucial for comprehending respiratory diseases, the mechanisms of action of respiratory drugs, and the impact of various medications on lung function.  Overview of the Respiratory System The respiratory system can be divided into two main parts: Upper Respiratory System : Includes the nose, pharynx, and associated structures. Lower Respiratory System : Includes the larynx, trachea, bronchi, and lungs. Functionally, the respiratory system also has two zones: Conducting Zone : Filters, warms, and moistens air and conducts it to the lungs. Includes the nose, pharynx, larynx, trachea, bronchi, bronchioles, and terminal bronchioles. Respiratory Zone : Site of gas exchange. Includes the respiratory bronch...