The lungs are a pair of air-filled organs located in the thoracic cavity, on the left and right side, separated by a central mediastinum, which contains the heart, thoracic parts of the great vessels, thoracic parts of the trachea, esophagus, thymus, and other structures.

It’s also important to notice that the heart is turned and extends towards the left side of the thoracic cavity, imposing on the left lung markedly more than the right so the anatomy of the two lungs is not completely symmetrical.

Each lung is covered by a membrane called the pleura, which is subdivided into the visceral pleura that intimately adheres to the lung and the parietal pleura that lines the pulmonary cavity.

Between them, there’s the pleural cavity, which is normally filled with a thin film of fluid.

Now, on the medial part of each lung, there’s the pulmonary hilum, where the root of the lung passes through.

The root of the lungs is made of structures like the main bronchus arteries, and veins.

The lungs are light, soft and spongy, and each of them has an apex a base, 3 surfaces: costal, mediastinal and diaphragmatic, and 3 borders: anterior, inferior and posterior.

The apex is the blunt superior end of the lung above the level of the first rib into the root of the neck, while the base is the concave inferior surface of the lung that rests on the diaphragm.

Now for the specifics.

The right lung is larger and heavier than the left, but it’s shorter and wider, because the right dome of the diaphragm is higher and the heart and pericardium are more to the left.

The right lung is divided into three lobes, superior, middle and inferior, by the horizontal fissure and the oblique fissure, which can be seen on all the surfaces of the lung.

On the other hand, the left lung has a single left oblique fissure, which can also be seen on all surfaces and divides the left lung into two lobes: superior and inferior.

Also on the left lung, there’s a deep cardiac notch on the anterior border, caused by the deviation of the heart towards the left.