Functional Anatomy in the Respiratory System
(or…. A more in-depth look at the organs)
The nasal cavity : the nasal cavity is divided by the nasal septum. Its base is formed by the palate, which separates it from the oral cavity. The roof is formed by the ethmoid and sphenoid bones of the skull - The nasal vestibule is just superior to the nostrils. This is where the hairs are found
- The rest of the cavity is lined with either olfactory mucosa (most of the superior region) or respiratory mucosa (rest of the cavity)
- Protruding medially from the lateral walls are the three conchae which increase the mucosal surface area. They also enhance air turbulence.
The pharynx : has three main regions based on location. The entire pharynx has a muscular wall of skeletal muscle, but the mucous membranes differ in the three regions. - Nasopharynx
is posterior to the nasal cavity, superior to the soft palate. The uvula closes off the nasopharynx during swallowing. It has a pseduostratified epithelium continuous with that of the nasal cavity. - Oropharynx
is posterior to the oral cavity and extends to the epiglottis. It is lined with stratified squamous epithelium. - Laryngopharynx
is posterior to the upright epiglottis and extends to the larynx. It is lined with stratified squamous.
The lungs : occupy the entire thoracic cavity except the mediastinum. Because of where the heart is located, the left lung is smaller than the right, and the left only has two lobes (upper & lower) while the right has three (upper, middle and lower). - Lungs are suppled with blood via the bronchial vessels which enter the lung through an indentation on the medial surface of each lung. That indentation is called a hilus.