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LUNGS

The Lungs is the essential respiratory organ in all air breathing

animal.

The organ without muscle is lungs.

The main function of the lungs is the oxygenation of blood and

to supply oxygen to it.

The lungs, nose, and trachea are part of the respiratory system

The trachea (windpipe) conducts inhaled air into the lungs

through its tubular branches, called bronchi.

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The bronchi divide into small branches called bronchioles.

The bronchioles end in clusters of microscopic air sacs called

alveoli.

Alveoli are small air sacs of the lungs through the wall of which

gaseous exchange takes place between blood and air.

The lungs are covered by a thin tissue layer called the pleura.

Inflammation of the lining of the lung (pleura) is called Pleurisy

which often causes pain when breathing in.

The right lung is larger than left lung.

Weight of the right lung is about 620gm.

Weight of the left lung is about 570gm.

The CO2 content in the air that we exhale is about 8%.

The exchange of O2 and CO2 takes place in at alveoli of lungs

The amount of air moving in and out of lungs during each breath

is called tidal volume.

The maximum volume or air that can be moved in or out of the

lungs is referred to as the vital capacity.

Eupnoea means Normal breathing

Dyspnea means Painful breathing

Anoxia means No oxygen in inspired air

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SARS (Severe Acute Respiratory syndrome) a lung disease is

caused by Corona virus. This virus first discovered in Asia in

2002.

Chronic obstructive pulmonary disease (COPD) is lungs

disease, it damage to the lungs results in difficulty blowing air

out, causing shortness of breath. Smoking is by far the most

common cause of COPD.

Pneumonia is an infection in one or both lungs. Bacteria,

especially Streptococcus pneumonia, are the most common

cause.