How many lobes does the left lung have?

The left lung is anatomically divided into two lobes: the upper lobe and the lower lobe. This is in contrast to the right lung, which has three lobes, consisting of the upper, middle, and lower lobes. The left lung's structure is adapted to accommodate the heart, which has a notable indentation on the medial side known as the cardiac notch. This anatomical configuration allows for more efficient gas exchange while also accommodating the unique position of the heart. Therefore, the answer indicating that the left lung has two lobes is correct, as it accurately reflects the anatomy of the lung in relation to the thoracic cavity. Understanding lung anatomy is crucial for perfusionists, as it plays a key role in respiratory function and the management of patients during cardiopulmonary bypass procedures.