Human Lung Biography
(Source google.com)
The human lungs are the organs of
respiration in humans. Humans have two lungs, a right lung and a left lung. The
right lung consists of three lobes while the left lung is slightly smaller
consisting of only two lobes (the left lung has a "cardiac notch" allowing
space for the heart within the chest). Together, the lungs contain
approximately 2,400 kilometres (1,500 mi) of airways and 300 to 500 million
alveoli, having a total surface area of about 70 square metres (750 sq ft) to
100 square metres (1076.39 sq ft) (8,4 x 8,4 m) in adults — roughly the same
area as one side of a tennis court. Furthermore, if all of the capillaries that
surround the alveoli were unwound and laid end to end, they would extend for
about 992 kilometres (616 mi). The lungs together weigh approximately 2.3
kilograms (5.1 lb), with the right lung weighing more than the left. The pleural cavity is the
potential space between the two serous membranes, (pleurae) of the lungs; the
parietal pleura, lining the inner wall of the thoracic cage, and thevisceral
pleura, lining the organs themselves–the lungs. The respiratory system includes
the conducting zone, which consists of all parts of the airway that conducts
air into the lungs. The parenchyma of the lung, only relates to the functional
alveolar tissue, but the term is often used to refer to all lung tissue,
including the respiratory bronchioles, alveolar ducts,terminal bronchioles, and
all connecting tissues. The lungs are located within the
thoracic cavity, on either side of the heart and close to the backbone. They
are enclosed and protected by the ribcage. The left lung has a lateral
indentation which is shaped to accommodate the position of the heart. The right
lobe is a little shorter than the left lung and this is to accommodate the
positioning of the liver. Both lungs have broad bases enabling them to rest on
the diaphragm without causing displacement. The right lung is divided into
three lobes (as opposed to two lobes on the left), superior, middle, and
inferior, by two interlobular fissures: The right lung has a higher
volume, total capacity and weight, than that of the left lung. Although it is
5cm shorter due to the diaphragm rising higher on the right side to accommodate
the liver, it is broader than the left lung due to the cardiac notch of the
left lung. The middle lobe is the smallest lobe of the right lung. It is
wedge-shaped, and includes the part of the anterior border, and the anterior
part of the base of the lung. The superior and inferior lobes are similar to
those of the left lung (which lacks a middle lobe.) On the mediastinal surface,
immediately above the hilum, is an arched furrow which accommodates the azygos
vein; while running superiorly, and then arching laterally some little distance
below the apex, is a wide groove for the superior vena cava and rightinnominate
vein; behind this, and proximal to the apex, is a furrow for the innominate
artery. Behind the hilum and the
attachment of the pulmonary ligament is a vertical groove for the esophagus;
this groove becomes less distinct below, owing to the inclination of the lower
part of the esophagus to the left of the middle line. In front and to the right of the
lower part of the esophageal groove is a deep concavity for the
extrapericardiac portion of the thoracic part of the inferior vena cava. 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.
There is also an area of the upper lobe of the lung, specific to the left lung called the lingula, meaning little tongue and is often referred to as thetongue in the lung. As seen on the surface, this fissure begins on the mediastinal surface of the lung at the upper and posterior part of the hilum, and runs backward and upward to theposterior border, which it crosses at a point about 6 cm. below the apex. It then extends downward and forward over the costal surface, and reaches the lower border a little behind its anterior extremity, and its further course can be followed upward and backward across the mediastinal surface as far as the lower part of the hilum. On the mediastinal surface, immediately above the hilum, is a well-marked curved furrow produced by the aortic arch, and running upward from this toward the apex is a groove accommodating the left subclavian artery; a slight impression in front of the latter and close to the margin of the lung lodges the left innominate vein. Behind the hilum and pulmonary ligament is a vertical furrow produced by thedescending aorta, and in front of this, near the base of the lung, the lower part of theesophagus causes a shallow impression.
There is also an area of the upper lobe of the lung, specific to the left lung called the lingula, meaning little tongue and is often referred to as thetongue in the lung. As seen on the surface, this fissure begins on the mediastinal surface of the lung at the upper and posterior part of the hilum, and runs backward and upward to theposterior border, which it crosses at a point about 6 cm. below the apex. It then extends downward and forward over the costal surface, and reaches the lower border a little behind its anterior extremity, and its further course can be followed upward and backward across the mediastinal surface as far as the lower part of the hilum. On the mediastinal surface, immediately above the hilum, is a well-marked curved furrow produced by the aortic arch, and running upward from this toward the apex is a groove accommodating the left subclavian artery; a slight impression in front of the latter and close to the margin of the lung lodges the left innominate vein. Behind the hilum and pulmonary ligament is a vertical furrow produced by thedescending aorta, and in front of this, near the base of the lung, the lower part of theesophagus causes a shallow impression.
Human Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker
Human Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker
Human Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker
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