respiration

The lungs, the spongy bodies, large and conical, play a vital role since they are responsible for the oxygen in the body. Oxygen combustion uses the human body, ie it allows fuel to burn the nutrients in food. The body produces and the energy needed to fill its needs.

The right lung has three lobes, while the left has only two, but has a location for the heart. The lungs may contain adult three liters of air around. These are the chest muscles that are responsible for the work of breathing as the lungs have no muscles themselves. Much of this work is done by a muscle end at the base of the lungs, the diaphragm. The involuntary and uncontrolled contraction of the muscle because the "hiccups". Breathing is an automatic phenomenon, present even when one is unconscious. At rest, the respiratory rate of the average adult is 16 breaths per minute.

The air that inspires it descends into the trachea to the bronchi, which separate

to enter the left or right lung. Bronchial themselves branch into several bronchioles, which are divided into half a dozen cellular channels, which are narrow conduits in the opening air sacs. This branched structure uniting the trachea and bronchi, the bronchioles, canals and alveolar air sacs is often called "bronchial tree" because of its resemblance to the branches and leaves of a tree. A dozen cells are clustered together on each bag honeycomb. This is in the thousands of tiny air sacs in the lungs, the oxygen provided by the inspiration through the membrane of the alveolar wall to be transferred to red blood cells in capillaries (small blood vessels on alveoli). Conversely, waste gases pass blood red air cells to be eliminated by the end. The cells are particularly susceptible to infection because they are a hot and humid environment conducive to the proliferation of viruses and bacteria. This explains why a simple cooling can develop into pneumonia or pneumonia *, which are characterized by infection and inflammation sometimes serious, can compromise the ventilation of the lungs. However, the body needs a constant supply of oxygen and nutrients costs to remain alive.