In the lung

Lung

The lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart...

, the oblique fissure (or major fissure) separates the inferior lobe of either lung from the remainder of the lung. (In the right lung

Right lung

The human right lung is divided into three lobes , superior, middle, and inferior, by two interlobular fissures:-Fissures:...

, it separates the inferior from the superior and middle lobe; in the left lung it separates the inferior and superior lobe, as there is no middle lobe in the left lung

Left lung

The human left lung is divided into two lobes, an upper and a lower, by the oblique fissure, which extends from the costal to the mediastinal surface of the lung both above and below the hilum....

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The oblique fissure extends from the spinous process of T2 (posteriorly) to 6th costal cartilage (anteriorly).