Each part has its own
function. The lungs fill most of the cest cavity and they
are protected by the flexible rib cage. They provide
oxygen from inhaled air to the capillaries and to exhale carbon dioxide
given from them. Air enters the lungs trough the
trachea just below the larynx. The right lung is
separated into 3 lobes. The left lung is separated into 2
lobes. So the lung's function is to pass oxygen
to the blood. The pulmonary vessels make blood
circulate trough the system especially through the lungs.
There is the inferior and superior pulmonary vein both of them return
blood to superior and inferior lobes of lungs. All veins
except pulmonary carry unaerated blood. Within the
breathing muscles is the Diaphragm the biggest respiratory muscle wich
is dome shaped. It is the major muscle that separates chest from
abdomen and it is used for inhaling. The Diaphragm is under the
lungs so when breathing it contracts and relaxes. The
intercostal muscles between the ribs change internal pressure by
lifting and relaxing rib cage in rythm with the
Diaphragm. There are 2 kinds of intercostal muscles
they are internal and external they move the chest and
lungs. In the air passages are the
bronchi. Primary bronchi form from the trachea
and enter the lungs where they become smaller and branch inside the
lungs. From the nose and mouth air passages meet in a
camber called the Pharynx. Then they lead into
2 new passageways 1 is open and the other one is guarded by a trapdoor
called Eppiglottis. The open passageway is is
called Esophagus leads to the stomach. The
guarded passageway is the Trachea that leads to
lungs. The Larynx is on top of the
Trachea and under the Epiglottis.
|
