00:01
This question asks us to identify what happens when the lungs become stiff and inelastic.
00:08
Well, when we really say that the lungs become stiff and inelastic, we're really referring to the alveoli.
00:13
Remember, these are the grape -like bundles at the ends of those bronchials.
00:20
And they are going to fill with air when we breathe in.
00:26
They're going to expand.
00:27
And they are going to allow for diffusion to occur between the alveoli, the air inside the alveoli, and the capillaries that are going to eventually lead back to the heart, bring oxygenated blood throughout the body, and take deoxygenated blood back to the lungs so that it can be exchanged and saturated with oxygen.
00:49
So what happens is when we say the lungs become stiff and elastic, the alveoli become inelis, in elastic.
01:01
So they lose their ability to expand as well.
01:04
Okay.
01:05
So it would appear.
01:09
You know, at first glance, you'd think, well, maybe that's going to cause some problems with the gas exchange, right? they're not expanding as well.
01:15
The gas exchange is not going to be as good as it was before.
01:20
Well, that is true to an extent, but i think there's a better answer here.
01:24
It's actually much simpler than that, right? the gas change might be limited in the sense that there might be less gas or less air in the alveoli, but not necessarily because not all the oxygen from that air is going to enter the capillaries, only a small percentage of it, because most of the air that we breathe out still is oxygenated.
01:52
So there is a better answer here.
01:55
I would not say that it has an effect on contraction or relaxation of the diaphragm, because the diaphragm is kind of independent of the lungs.
02:03
The diaphragm is going to move up and down, and it is going to change the size of the chest cavity...