How is the anatomy of capillaries and capillary beds well suited to their function?

Video transcript

Hey, everyone. Let's take a look at this question together which cells form the inner lining of the capillary walls and are responsible for the efficient exchange of substances between the blood and the surrounding tissues. Is it answer choice. A parasites answer choice. B erythrocytes answer choice. C, endothelial cells or answer choice. D epithelial cells. Let's work this problem out together to try to figure out which of the following types of cells is the correct one. So we are looking for the type of cell that formed the inner lining of the capillary walls and are responsible for the efficient an exchange of substances between the blood and the surrounding tissues. While looking at our answer choices, we can immediately eliminate answer choice. A parasites since parasites are contractile cells that are found around the endothelial cells and help to regulate blood flow and are not responsible for the exchange of substances. And answer choice. B erythrocytes can be eliminated as well. Since those erythrocytes are our red blood cells, which function to transport oxygen from the lungs to the tissues and remove carbon dioxide, which leaves us with endothelial cells and epithelial cells. And we know that epithelial cells are the cells that make up that epithelial tissue, which is a type of tissue that lines the surface and cavities of organs. And they are involved in protection, absorption and secretion, sensation and filtration and not the efficient exchange of substances between the blood and ceramic tissues. So answer choice D can be eliminated leaving us with the only remaining answer choice, which is the correct answer. Answer choice c endothelial cells. Since those endothelial cells are the cells that form that inner lining of the capillary walls and allow for that efficient exchange of the substances between the blood and the surrounding tissues. I hope you found this video to be helpful. Thank you and goodbye.