Unit 8. Parents and young children. p.74
Vocabulary: Alcohol ; Speaking: Dealing with a defensive patient
Reading: The Lungs; Writing: Writing accurately for training or work
application
The Lungs
The lungs are the main organs of the respiratory system. There are two
lungs in the human body located in the lateral cavities of the chest. The lungs
are separated from each other by the mediastinum. The lungs are covered with
the pleura. They are conical in shape. Each lung has the base, apex, two borders
and three surfaces.
The lung has the apex extending upward 3-4 centimetres (cm) above the
level of the first rib. The base of the lung is located in the convex (выпуклый)
surface of the diaphragm.
The posterior borders of the lungs are on each side of the spinal column.
The anterior borders thin and overlap (перекрывать) the pericardium.
The weight of the lungs varies according to many conditions. In the
adult male the weight of the lungs is about 1,350 grams (g). The right lung
is about 15% heavier than the left one. The vital capacity of the lungs is 3.5-
4.0 litres (1) in the male and it is 3.0-3.5 litres in the female.
The right lung consisting of three lobes is heavier than the left one
because the latter consists only of two lobes. The lower lobe of the left lung
is larger than the upper one.
In infants the lungs are of a pale rose colour, but later they become
darker.
The lung is covered with an external serous coat, i.e. with visceral layer
of the pleura. The parenchyma or proper substance of the lungs consists of
the bronchial tree with elastic tissue and vessels.
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