Introduction

This topic covers the basic structure and function of the respiratory system. It mainly focuses on the structure of the trachea, bronchioles, bronchii and alveoli, and on how air is conditioned and transported in the conduction part of the respiratory system, before arriving in the respiratory portion of the lung, where gas exchange takes place between the blood and air.

Objectives

After following this topic, and any additional reading, you should know

1. The inter-relationships and functions of the different components of the respiratory system.
2. The histological structure of the succession of airways and air conducting passages, and be able to recognize bronchi and bronchioles in lung sections and explain their different structures.
3. The histological structure of the different parts of the respiratory system and understand how this is adapted to its function, in particular: how the histological organisation of the interalveolar wall (septum) is important for gaseous exchange and the functional significance of secretory epithelial cells of interalveolar walls.
4. How changes occurring in the course of some common diseases may affect the structure and functioning of the respiratory system.