Where are a rat’s lungs located? - briefly
In a rat, the lungs reside within the thoracic cavity, positioned behind the sternum and flanked by the rib cage, connected to the trachea through the primary bronchi. They are enclosed by the pleural membranes that line the chest wall.
Where are a rat’s lungs located? - in detail
The lungs of a laboratory rat occupy the thoracic cavity, situated between the rib cage anteriorly and the vertebral column posteriorly. They rest on the dorsal surface of the diaphragm, which forms the inferior boundary of the respiratory space. The sternum and costal arches provide the ventral enclosure, while the intercostal muscles and pleural membranes maintain the airtight compartment required for ventilation.
Each lung is divided into distinct lobes. The right lung consists of four lobes—cranial, middle, caudal, and accessory—while the left lung contains a single, larger lobe that occupies most of the left hemithorax. The lobes are separated by thin interlobar fissures and are enveloped by visceral pleura. The visceral pleura adheres to the lung surface, whereas the parietal pleura lines the thoracic wall, mediastinum, and diaphragm, creating the pleural cavity filled with a lubricating fluid.
Key anatomical relationships:
- Diaphragm: Forms the floor of the thoracic cavity; lungs rest directly upon it.
- Mediastinum: Contains the heart, trachea, esophagus, and major vessels, positioned between the two lungs.
- Rib cage: Provides rigid protection; the lungs expand outward during inspiration.
- Pleural membranes: Ensure low‑friction movement and maintain negative intrapleural pressure.
Blood supply reaches the lungs via the pulmonary arteries, which branch from the right ventricle through the pulmonary trunk, while bronchial arteries deliver oxygenated blood to the lung tissue itself. Venous drainage occurs through pulmonary veins returning oxygen‑rich blood to the left atrium.
Innervation is provided by the vagus nerve, which conveys sensory information and modulates bronchoconstriction. The respiratory muscles—intercostals and diaphragm—are coordinated by the brainstem respiratory centers to achieve the rhythmic inhalation and exhalation required for gas exchange.