Unit 9 – Introduction to Respiratory System Tissues

Introduction to Respiratory System Tissues

The respiratory system consists of all passageways that conduct air into and out of the lungs during the process of ventilation (inhalation and exhalation), and the tissues within the lungs involved in gas exchange between air and blood.  The human respiratory system is divided anatomically into the upper and lower respiratory system.  The upper respiratory system consists of all respiratory structures superior to the epiglottis, including the mouth (oral cavity), nose, nostrils, nasal cavity, paranasal sinuses, and pharynx (throat).  The lower respiratory system consists of all respiratory structures inferior to the epiglottis, including the larynx (voice box), trachea, bronchi, bronchioles, and alveoli within lung tissue where gas exchange occurs between air and the bloodstream.  The respiratory muscles responsible for changing the volume of the thoracic cavity during ventilation can also be considered part of the respiratory system.

The tutorials in this unit will focus on the structure and function of respiratory passageways of the lower respiratory system, specifically the trachea, bronchi, and bronchioles, and the structure and function of alveoli within lung tissue where gas exchange occurs.