The lungs get oxygen from the environment to the blood stream. They provide an interface between those two spaces. Oxygen crosses through the alveoli into the pulmonary capillaries, and carbon dioxide goes the opposite way so that you can get rid of it.
I agree with WWD – there are so many complexities regarding pulmonary function that you need to be more specific in your question. Are you interested in ventilatory mechanisms, ventilation/perfusion ratios, or diffusion of gases?
well,if you mean the human lung Breathing ,is largely driven by the muscular diaphragm at the bottom of the thorax. Contraction of the diaphragm pulls the bottom of the cavity in which the lung is enclosed downward. Air enters through the oral and nasal cavities; it flows through the larynx and into the trachea, which branches out into bronchi. Relaxation of the diaphragm has the opposite effect, passively recoiling during normal breathing. During exercise, the diaphragm contracts, forcing the air out more quickly and forcefully. The rib cage itself is also able to expand and contract to some degree, through the action of other respiratory and accessory respiratory muscles. As a result, air is sucked into or expelled out of the lungs, always moving down its pressure gradient. This type of lung is known as a bellows lung as it resembles a blacksmith’s bellows.
The lungs have many small ball-like folds inside of them called alveoli which give the lungs a surface area the size of a tennis court. These alveoli have capillaries (very small arterioles) all over their surface. Capillaries have a wall that is only one cell think, as do the walls of the alveoli.
Inside of the capillaries is deoxygenated blood from the right side of the heart which had previously come from the rest of the body. The red blood cells in this are able to pick up oxygen and release carbon dioxide. As you breathe in, gaseous exchange occurs, oxygen diffuses down the conc. gradient into the blood while carbon dioxide diffuses into the lungs. The blood is the oxygenated and returns to the left side of the heart to be pumped to the rest of the body.
Medical school in a nutshell: Air goes in and out, blood goes round and round, and if those don’t happen, it probably ain’t good.
I’d suggest you refine your question for more specific and appropriate answers. You may want to look at the anatomy of the airway first, then the pulmonary circulation, and then gas exchange at the capillary/alveolar level, just for starters, and return to this venue with more specific questions.
Greetings..lungs is functioning in respiratory or breathing process….for more information you can go to this website at
what a long story!
There is a book by West called respiratory physiology. It is about 200 pages long and will tell you all you need to know.
by the use of positive and negatve air pressure to get the air into the lungs.
It’s why we have a diaphragm and why, if we get winded we can’t breathe!
Then the little air bags (alveoli) do their job to exchange gases using concentration gradients and things like that.
Simple but effective and God am I glad it works!! haha