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( Lung)
The lung is the essential respiration organ in air-breathing animals, including most tetrapods, a few fish and a few snails. The most primitive animals with a lung are the lungfish (vertebrate) and the pulmonate snails (invertebrate). In mammals and the more complex life forms, the two lungs are located in the chest on either side of the heart. Their principal function is to transport oxygen from the atmosphere into the bloodstream, and to release carbon dioxide from the bloodstream into the atmosphere. This exchange of gases is accomplished in the mosaic of specialized cells that form millions of tiny, exceptionally thin-walled air sacs called alveoli. Medical terms related to the lung often begin with pulmo-, from the Latin pulmonarius ("of the lungs"), or with pneumo- (from Greek p?e?µ? "breathe") The lungs are very important. Energy production to aerobic respiration requires oxygen and glucose and produces carbon dioxide as a gaseous waste product, creating a need for an efficient means of oxygen delivery to cells and excretion of carbon dioxide from cells. In small organisms, such as single-celled bacteria, this process of gas exchange can take place entirely by simple diffusion. In larger organisms, this is not possible; only a small proportion of cells are close enough to the surface for oxygen from system]] that centralized the task of obtaining oxygen from the atmosphere and bringing it into the body, whence it could rapidly be distributed to all the circulatory system. The lungs also In air-breathing vertebrates, respiration occurs in a series of steps. Air is brought into the animal via the airways — in reptiles, birds and mammals this often consists of the nose; the pharynx; the larynx; the trachea (also called the windpipe); the bronchi and bronchioles; and the terminal branches of the respiratory tree. The lungs of mammals are a rich lattice of alveoli, which provide an enormous surface area for gas exchange. A network of fine capillaries allows transport of blood over the surface of alveoli. Oxygen from the air inside the alveoli diffuses into the bloodstream, and carbon dioxide diffuses from the blood to the alveoli, both across thin alveolar membranes. The drawing and expulsion of air is driven by muscular action; in early tetrapods, air was driven into the lungs by the pharyngeal muscles, whereas in reptiles, birds and mammals a more complicated musculoskeletal system is used. In the mammal, a large muscle, the diaphragm (in addition to the internal intercostal muscles) drives ventilation by periodically altering the intra-thoracic volume and pressure; by increasing volume and thus decreasing pressure, air flows into the airways down a pressure gradient, and by reducing volume and increasing pressure, the reverse occurs. During normal breathing, expiration is passive and no muscles are contracted (the diaphragm relaxes).
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Lung Subcategories
Lung Articles
A Look At Treatment For Lung Cancer by Jon Simms
Cancer is a disease in which certain body cells don't serve right, division very swift, and goods too much hankie that forms a lump. The lungs, a brace of clean-like, shaft-shaped organs, are part of the body's respiratory structure. When we breathe ...
Top 10 Health Benefits of Tea by William Lengeman
Tea (to borrow a catchphrase) does a body good. While some marketers tend to place undue emphasis on just how much good tea can do us, there's compelling evidence nonetheless to show that it can benefit our health on a number of fronts. Here are so...
Smoking -- More Than Just a Simple Lung Problem by Robert Melkonyan
A person was not born to live alone and completely isolated from society however, certain attitudes and addictions can surely create this illusion as many people will try to avoid dealing with someone who is a heavy smoker, the reasons are plenty and...
Cancer, Understanding It, Coping With It. by Michael Lyall
So you or a member of your family may unfortunately have been diagnosed with Cancer. The big ‘C’ some people call it. Why is this word so difficult to say?
No longer does cancer automatically mean a death sentence. Survival rates have grown c...
Drinking Red Wine Is Good For Your Heart, Lungs, Kidneys, Brain And More... by Paul Rodgers
Red wine benefits are numerous and plentiful. Red wine benefits are generally good for you, but it is important to know the specifics of these benefits because you can then employ them to serve your body...
The Best Way to Burn Calories by Yuri Elkaim
One of the best ways to burn more calories in your workouts is simply to use more full body movements. The reason for this is simple. Your body burns 5 calories for every liter of oxygen it consumes and the more muscle required for a given movement...
What Is Sarcoidosis? by Peter Hutch
Sarcoidosis, also called sarcoid (from the Greek 'sark' and 'oid' meaning "flesh-like") or Besnier-Boeck disease, is an immune system disorder characterised by non-caseating granulomas (small inflammatory nodules) that most commonly arises in young a...
Information About Various Types of Cancer by Peter sams
Cancer
The organs and tissues of the body are made up of tiny building blocks called cells. Cancer is a disease of these cells. Cells in different parts of the body may look and work differently but most reproduce themselves in the same way. ...
Top 7 Tips To Take The Plunge Towards Healthy Habits by Raymond Lee
Okay, you are committed. You have gone public and recruited a few buddies. You know what triggers your binges, and you have devised ways to avoid them. You have successfully maintained your habit without allowing it to get worse. Now it is time to ge...
How to Cure and Control Asthma by Tenskaw Harding
Asthma is defined as a chronic respiratory disease, often arising from allergies, that is characterized by sudden recurring attacks of labored breathing, chest constriction, and coughing. Asthma can be fatal if not treated. With the proper treatme...
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