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Why does the left lung have fewer lobes than the right lung?
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Respiratory system
Different methods of respiration in animals.
The left lung has fewer lobes than the right lung primarily due to the asymmetrical placement of the heart within the chest cavity.12
While the right lung is composed of three lobesāthe superior, middle, and inferiorāthe left lung is slightly smaller in volume and contains only two lobes to accommodate the space occupied by the heart. Both lungs are situated within the thoracic cavity and are separated by the mediastinum, a connective tissue space that houses the heart, major blood vessels, and other structures.12