Alveoli and capillaries relationship advice

Oxygen movement from alveoli to capillaries (video) | Khan Academy

Covering each alveolus is a whole network of little blood vessel called capillaries , which are very small branches of the pulmonary arteries. It is important that the. The layers of cells lining the alveoli and the surrounding capillaries are each only one cell thick and are in Gas Exchange Between Alveoli and Capillaries. Relationship of Structural to Functional Impairment during Alveolar-Capillary Membrane .. We thank Dr. Wayne Mitzner for his kind advice that assisted with.

Effects of Aging on the Respiratory System The primary function of the respiratory system is to exchange oxygen and carbon dioxide. Inhaled oxygen enters the lungs and reaches the alveoli. The layers of cells lining the alveoli and the surrounding capillaries are each only one cell thick and are in very close contact with each other. Oxygen passes quickly through this air-blood barrier into the blood in the capillaries. Similarly, carbon dioxide passes from the blood into the alveoli and is then exhaled.

Oxygenated blood travels from the lungs through the pulmonary veins and into the left side of the heart, which pumps the blood to the rest of the body see Biology of the Heart: Function of the Heart.

Oxygen movement from alveoli to capillaries

These are the cells that are also kind of pancake shaped. And these are going to make the walls of the capillary. From there, the oxygen molecule goes into the plasma and then finally gets into the red blood cell.

Gaseous exchange between alveoli and capillaries

And of course, the red blood cells are packed full of hemoglobin. So this is a little hemoglobin protein here. And this hemoglobin has four spots on it. It's going to allow four molecules of oxygen to bind it. And so once our oxygen gets there, it's going to hope to find some hemoglobin that it's got a little free spot. And once it binds to the hemoglobin, the red blood cell is going to now carry that oxygen out to the rest of the body, wherever it's needed. So that's kind of how oxygen gets from the alveolus out to the body.

Now, let me make a little bit of space. I'm going to show you what I want to do. I want to do kind of an interesting thing here. Hopefully, it'll help you understand this journey that the oxygen molecule is taking a little bit better. So let's imagine something like this, where you've got a nice little rectangle. I'm going to try to draw this rectangle out on the side for you, in kind of the same way I'm drawing it here.

Relationship of Structural to Functional Impairment during Alveolar-Capillary Membrane Development

So just keep your eye on the colors, because I'm not going to relabel anything, just to kind of keep it nice and easy. What I'm going to do is just imagine that the oxygen is starting at the top of this rectangular three-dimensional square-like object I'm drawing, I guess, a three-dimensional cube, rectangular cubed.

And then it's got to get to the bottom of this rectangular cube. So at the bottom, we've got the red blood cell and the hemoglobin.

That's the last layer down here. And the top layer was the alveolus or the gas. So I actually sketched that in as well. And so that would be the very top layer.

And it has to get through all these layers. This blue layer, for example, this is that liquid that's lining the inside of the alveolus.

The Circulatory System

And let me draw a molecule of oxygen starting its journey up here. That's the gas phase, right. So it has to actually get from the gas stage through the liquid layer, into the next layer, which is the epithelial cell. That's this guy right here.

Relationship of Structural to Functional Impairment during Alveolar-Capillary Membrane Development

That's the second layer. Third layer, we said was the base membrane. I'm just kind of going through them one by one. And this is also kind of a nice way of a review, I suppose, as well. Then you have all that connective tissue, a nice, thick layer of connective tissue.

And remember, the base membrane and the connective tissue, they're both chock full of proteins, different types of proteins. But both are there for structural support. Got some more base membrane here on this side, and this is going to be right before you get to the endothelial cells.

That was the endothelial layer. This is the cell that kind of offers the capillary walls. And then we've got some plasma, we said. The oxygen has to get through some plasma and finally is going to get into the red blood cell. So this whole bit, the reason I'm even drawing it like this or taking the time to draw it like this is that this entire layer right here-- this is all liquid. This is all liquid and predominately water.

So remember, our bodies are heavily water-based. So our molecule literally is going from gas, which is at the top of our rectangular cube, all the way down through many, many different layers of liquid. So it kind of makes it easy, if you can divide it into these two categories, gas and liquid. Published by Elsevier Inc. This document may be redistributed and reused, subject to certain conditions.

  • Lungs and Respiratory System

This article has been cited by other articles in PMC. Abstract Bronchopulmonary dysplasia is a chronic lung disease of extreme preterm infants and results in impaired gas exchange. Although bronchopulmonary dysplasia is characterized histologically by alveolar-capillary simplification in animal models, it is clinically defined by impaired gas diffusion.

With the use of a developmentally relevant model, we correlated alveolar-capillary structural simplification with reduced functional gas exchange as measured by the diffusing factor for carbon monoxide DFCO. At day 56, DFCO was measured as the ratio of carbon monoxide uptake to neon dilution, and lungs were fixed for histologic assessment of alveolar-capillary development.