General Anatomy of the Respiratory System – Module S1.5

General Anatomy of the Respiratory System – Module S1.5

The respiratory system is a complex system that includes organs that help the body exchange gases, specifically to absorb oxygen and expel carbon dioxide. The respiratory system consists of the following main components:

1. Nose:

• External nose: Includes the nasal bones, nasal cartilages, frontal process, septal cartilage, lateral nasal cartilages, lesser alar cartilages, greater alar cartilages, accessory nasal cartilages, and the nasal notch of the maxillary bone.

• Nasal cavity: A hollow space located within the skull, connecting with the external nose through the anterior nasal aperture and with the nasopharynx through the posterior nasal aperture. The nasal cavity has a roof, floor, lateral wall, and medial wall.

• Roof: Separates the nasal cavity from the skull.

• Floor: Separates the nasal cavity from the oral cavity.

• Lateral wall: Contains the superior, middle, and inferior nasal conchae and the superior, middle, and inferior nasal meatuses.

• Medial wall: The nasal septum, dividing the nasal cavity into two halves.

• Nasal mucosa: Covers the entire nasal cavity, consisting of the olfactory region and respiratory region.

• Paranasal sinuses: Hollow cavities located in the skull, communicating with the nasal cavity. They include:

• Frontal sinuses: Located in the frontal bone, above the eyes.

• Maxillary sinuses: The largest sinuses, located in the maxillary bone, next to the nose.

• Anterior and posterior ethmoidal sinuses: Located between the frontal and sphenoid sinuses, visible from the eye side.

• Sphenoid sinus: Located behind the ethmoidal sinuses, close to the sphenoid bone.

2. Larynx:

• The airway segment located between the pharynx and the trachea.

• The main organ of voice production.

• Located in the anterior neck, opposite cervical vertebrae III, IV, V, and VI.

3. Trachea:

• The airway tube connecting the larynx to the lungs.

• Boundaries:

• Superior: Cricoid cartilage (C6).

• Inferior: Where the trachea divides into the main bronchi, between thoracic vertebrae T4-T5.

• It has a cervical and a thoracic portion.

4. Main bronchi:

• Divided into two branches: Left main bronchus and right main bronchus.

• Right main bronchus: Larger, shorter, steeper, and has more branches than the left main bronchus.

5. Lungs:

• Located in the chest cavity, bordering the mediastinum.

• External morphology:

• Costal surface: Includes the horizontal fissure (right lung) and oblique fissure.

• Diaphragmatic surface: Adjacent to the diaphragm.

• Mediastinal surface: Adjacent to the mediastinum.

• Apex of the lung: The uppermost part of the lung, extending above the clavicle.

• Anterior/inferior border: The marginal part of the lung.

• Lung root: Includes the functional and nutritional lung root.

• Functional lung root: Includes the main bronchus, pulmonary artery, and pulmonary veins.

• Nutritional lung root: Includes bronchial arteries and veins, autonomic nerves (pulmonary plexus), and lymphatic vessels.

6. Pleura:

• Encloses the lungs, consisting of two layers:

• Visceral pleura: Adheres to the lung surface.

• Parietal pleura: Adheres to the chest wall.

• Pleural cavity: The space between the two pleural layers, containing a small amount of pleural fluid to facilitate smooth lung function.

Note: This information is just a basic overview of the respiratory system. To understand the structure and function of the respiratory system in greater depth, further study of specialized literature is required.