human anatomy?

Question

what is it about the structure of the alveoli that makes them an ideal site for gas exchange?

Answer 1

The alveoli are the final branchings of the respiratory tree and act as the primary gas exchange units of the lung. The gas-blood barrier between the alveolar space and the pulmonary capillaries is extremely thin, allowing for rapid gas exchange. To reach the blood, oxygen must diffuse through the alveolar epithelium, a thin interstitial space, and the capillary endothelium; CO2 follows the reverse course to reach the alveoli.

Answer 2

After the 22 branching of the bronchus in the lungs reaching to the alveolar structures which are large in numbers, they have a large surface area because it is rounded and it has mini folds in the walls and these increase surface are for gaseous exchange.
The mucous and fluid secreting cells secrete to provided a moistened atmosphere to facilitate the diffusion of the O2 and CO2 gases through the walls of the alveoli.
The walls of the alveoli is a one cell thick epithelium layer this also facilitates diffusion.
The pressure between the alveoli and the capillaries surrounding it will increase the exchange rate,
There is a damp supply of cappillaries with blood passing throught waiting for the exchange of gases and purification of the blood.
So the main points are :-
1)surface area
2)pressure difference
3)damp cappilary supply
4)thin walled epithelium layer
5)large number of alveoli present

Answer 3

Well it is a combination of several things. First off they are very close to capillaries. Second they are continuously secreting a mucous to aid in the crossing of O2 and CO2. Third they are round which allows for greater surface area.

This wouldn't be a homework question now would it?

Answer 4

They are thin walled, protruding into the air stream of the lungs, and are richly endowed with capillaries for the gas transfer.

Answer 5

gross dissection human anatomy class

Answer 6

Some good answers above :)