Chapter 27 focuses on the respiratory system, outlining its structures, functions, and physiological processes like oxygenation and ventilation. It details assessment techniques, including physical examination, interpreting findings that indicate inadequate oxygenation, and considering age-related changes. Furthermore, it explains various diagnostic studies, such as blood gas analysis, oximetry, sputum tests, skin tests, endoscopy, and pulmonary function tests, used to evaluate respiratory health. The content is presented with learning outcomes, key terms, and case studies to facilitate understanding.