Dear Twitpic Community — thank you for all the wonderful photos you have taken over the fly yoga pj. We have now placed Twitpic in an archived state.

Theatr Gen Creu ar Daith: Pwy ’Sgrifennodd Honna? What’s Love Got to Do with It? Follow the link for more information. This is the latest accepted revision, reviewed on 8 March 2019. The lungs are the primary organs of the respiratory system in humans and many other animals including a few fish and some snails.

Humans have two lungs, a right lung and a left lung. They are situated within the thoracic cavity of the chest. The right lung is bigger than the left, which shares space in the chest with the heart. The lungs together weigh approximately 1. The tissue of the lungs can be affected by a number of diseases, including pneumonia and lung cancer.

In embryonic development, the lungs begin to develop as an outpouching of the foregut, a tube which goes on to form the upper part of the digestive system. The lungs are located in the chest on either side of the heart in the rib cage. They are conical in shape with a narrow rounded apex at the top, and a broad concave base that rests on the convex surface of the diaphragm. Both lungs have a central recession called the hilum at the root of the lung, where the blood vessels and airways pass into the lungs. The lungs are surrounded by the pulmonary pleurae. The main or primary bronchi enter the lungs at the hilum and initially branch into secondary bronchi also known as lobar bronchi that supply air to each lobe of the lung. The right lung has both more lobes and segments than the left.

It is divided into three lobes, an upper, middle, and a lower, by two fissures, one oblique and one horizontal. The upper, horizontal fissure, separates the upper from the middle lobe. The lower, oblique fissure, separates the lower from the middle and upper lobes, and is closely aligned with the oblique fissure in the left lung. The mediastinal surface of the right lung is indented by a number of nearby structures.

The heart sits in an impression called the cardiac impression. The 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. The mediastinal surface of the left lung has a large cardiac impression where the heart sits. This is deeper and larger than that on the right lung, at which level the heart projects to the left. On the same surface, immediately above the hilum, is a well-marked curved groove for the aortic arch, and a groove below it for the descending aorta.

The left subclavian artery, a branch off the aortic arch, sits in a groove from the arch to near the apex of the lung. The lobes of the lungs can be seen, and the central root of the lung is also present. High-resolution CT scans of a normal thorax, taken in the axial, coronal and sagittal planes, respectively. The lungs are part of the lower respiratory tract, and accommodate the bronchial airways when they branch from the trachea. The lungs include the bronchial airways that terminate in alveoli, the lung tissue in between, and veins, arteries, nerves and lymphatic vessels. All of the lower respiratory tract including the trachea, bronchi, and bronchioles is lined with respiratory epithelium.