An online study guide to learn about the structure and function of the respiratory system using interactive animations and diagrams.
An introduction to the nose and the nasal cavity. The nose is the first portion of the respiratory tract and serves as a vent for air exchange. Inhaled air is warmed, moistened, and cleaned so it can travel safely into other parts of the respiratory tract.
The nasal cavity is posterior to the nose and is framed and supported by several bones and cartilages. The nasal septum divides the nasal cavity into two chambers.
The nose is supported by upper and lower cartilages along with the maxilla and nasal bones. A pair of nasal bones support the bridge of the nose and the medial plates and frontal processes of the maxilla bones support the sides of the nose.
There are three turbinates on each side of the nasal cavity (Superior, middle, and inferior). Grooves are found between the curved turbinates. During inhalation, air is directed over and under the turbinates. The surface mucosa conditions or prepares the air so it can safely travel into the lungs.
An interactive demonstration of the Paranasal Sinuses and Sinusitis featuring the iconic GBS illustrations. Each image highlights and labels the sinuses in coronal and sagittal view.
The vestibule is the portion of the nasal cavity that lies directly posterior to the external nares. It is lined by stratified squamous epithelium providing as a barrier that helps protect the vestibule from damage. A layer of mucus typically covers the outer surface of the vibrissae.
Inside the nasal cavity, the surfaces of the turbinate bones (= nasal conchae) and meatuses are lined by respiratory mucosa (= nasal mucosa).
The olfactory mucosa detects odor-producing chemicals. The epithelium layer includes specialized nerve cells and non-motile cilia to provide a binding site for odorants. Mucus covers the receptor cilia where odorants dissolve and bind to cilia receptors. The binding produces an electrochemical impulse.
Air is conditioned to safely pass into the respiratory system by the nasal mucosa. Air is warmed and humidified. Mucus that is secreted traps foreign particles and then is moved by cilia to the throat.