Of course, the lungs receive a full flow of blood straight from the heart, because the entire blood supply must be oxygenated and have it's carbon dioxide removed continuously. The alveolis' function is to provide a large surface area for the gas exchange to take place. These millions of tiny air sacs have a surface covered in very fine capillaries.Their combined surface area is about the same as a tennis court,co-incidently similar to the surface area in the small intestine.
Alveoli are the air sacs inside lungs which are the actual places for exchange of gases (i.e. addition of Oxygen from air and removal of Carbon Dioxide)
Thus, the alveoli need to be very richly supplied with blood capillaries so that blood can flow in them and the gases inside them (CO2 in deoxygenated blood and O2 in oxygenated blood) can be fully exchanged.
Without these tiny blood vessels, there would be no other way through which exchange of these gases could take place.
the lungs supply the blood with oxygen, within the lungs there are alveoli which have a very thin membrane which allows oxygen to pass into the capillaries that run into the lungs hope i helped
The three ways that the lungs absorb gasses are...very moistthe alveoli have a big surface areaand finally...good blood supply
---------------------------- The exchange of gasses takes place across the Alveoli, which are air spaces surrounded by very small air sacs and have a rich supply of blood, because they are surrounded by capillaries. The lungs are made up of many alveoli which are the respiratory surface. Oxygen diffuses from the alveoli into the blood in the capillaries and carbon dioxide diffuses from the blood in the capillaries into the alveoli.
The air sacs (alveoli) have a very large total surface area and a very good blood supply. There is an exchange of gases between the air sacs and their surrounding capillary blood vessels. Oxygen diffuses from the air sac into the blood. Carbon dioxide diffuses from the blood into the air sac.
The tiny blood vessels that surround the alveoli arecalled alveolar capillaries
There are about 300 million alveoli in each of your lungs. These tiny air sacs provide an ideal site for the diffusion of gases into and out of the blood - also known as gaseous exchange. The alveoli have a very large surface area - in fact if all of the alveoli in your lungs were spread out flat they would cover the area of a tennis court. This large surface area is the result of all the alveoli being small spheres - it is another example of the importance of the surface area- to-volume ratio. If your lungs were simply two large balloon-like structures, the surface area wouldn't be big enough for you to get enough oxygen by diffusion to supply the needs of your cells. But each alveolus is a very tiny sphere. The smaller the radius of a sphere, the bigger the relative surface area - halving the radius increases the relative surface area by a factor of four. The millions of tiny alveoli in the human lungs are a very effective adaptation which provides a huge surface area for gaseous exchange into and out of the blood. The alveoli have a good air supply from the bronchioles and a rich blood supply. This is vital for successful gaseous exchange because it maintains a steep concentration gradient for oxygen from the air in the alveoli to the blood, and for carbon dioxide from the blood to the alveoli.
Alveoli are the tiny sacs in the lungs that are the powerhouses of the respiratory system. That is where oxygen-spent blood gives up its carbon dioxide and becomes re-charged with oxygen. Lung alveoli are the ends of the respiratory tree, branching from either alveolar sacs or alveolar ducts, which like alveoli are both sites of gas exchange with the blood as well. Alveoli are particular to mammalian lungs.
the blood surround Alveoli in order to gas exchange between the Alveoli and red blood cell.
the paouch like air secs at the smallest lenchioles is called alveoli.the walls of alveoli are very thin and they are sorrounding thin blood capllaries .it is in alveoli exchange of gaseouse takes place there are so many alveoli in blood so they provides very larges surface srea for cxchanges of gaseouse
Gas exchange takes place inside the lungs in the alveoli. The alveoli are a "grape like" structure at the very end of the respiratory tract. The alveoli are composed of a very thin membrane that separates the blood vessels from the gas chambers. The thin membrane allows diffusion of oxygen into the blood stream and diffusion of carbon dioxide (CO2) out of the blood stream. Once the CO2 has diffused into the alveoli, it is exhaled.
The alveoli and capillaries in the lungs pass oxygen to the blood. Both have very thin walls, which allow the oxygen to pass from the alveoli to the blood. The capillaries then connect to larger blood vessels, called veins, which bring the oxygenated blood from the lungs to the heart.
The Alveoli in the lungs have a very good capillary network because this is where gas exchange occurs. There needs to be sufficient area to allow the red blood cells to expel their carbon dioxide and to receive oxygen across the capillary and alveoli walls.