MODULE SUPPLEMENT: PULMONARY SYSTEM
Introduction

This module within the Biology/Physiology of Aging series focuses on the Respiratory system. Like the cardiovascular system, the lungs are active both day and night throughout ones lifetime. Rossi and colleagues (1996) note that 20,000 liters of air have daily contact with the airway and alveolar wall while the entire cardiac output crosses the pulmonary circulation. The lungs also are chronically exposed to environmental assaults, such as pollution and smoke; we do not have a choice about whether to breath or not in a given situation. Thus, it's often difficult to tease apart what happens with aging by itself and what changes are caused by various exposures. However, pulmonary function is extremely important in terms of our everyday functioning, and an understanding of what happens over time provides a basis for our clinical assessments and interventions. Given this introduction, the purpose of the current module is to describe and discuss changes that occur with age in the absence of pathology, and what this means in terms of physiological functioning.