Explanation There are three types of capillaries, differentiated by the ease at which substances can move through their walls and the structural differences that make up their greater or lesser permeability. Continuous capillaries- In most tissues and organs, such as the skeletal muscles, lungs, and brains, continuous capillaries occur. A thin layer of protein-carbohydrate, the basal lamina, surounds and separates the endothelium from the surrounding connective tissues. Narrow intercellular clefts around 4 nm long divide the endothelial cells. Small solutes like glucose can move across these clefts, but they hold back plasma proteins, platelets and other large molecules, and blood cells. Fenestrated capillaries- The endothelial cells present in the fenestrated capillaries are riddled with holes called pores of filtration...

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Question

Chapter 21, Problem 21.1.8AYLO

Summary Introduction

To analyze:

The distinction between continuous capillaries, fenestrated capillaries and sinusoids.

Introduction:

Materials such as food, waste and hormones must move through the walls of the vessels within the blood and the tissue fluids for any reason. The wall is too dense for sufficient movement of chemicals within the bloodstream and tissue fluid in almost all the larger vessels. The capillaries of the blood consist only of a basal lamina and an endothelium. Their walls are as thin a micrometer as 0.2 to 0.4. They average at the proximal end around 5 micrometers in diameter, widen at the distal end to around 9 micrometers, and often branch off along the way.

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Chapter 21, Problem 21.1.7AYLO

Chapter 21, Problem 21.1.9AYLO

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HUMAN ANATOMY

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Solution Summary: The author explains the differences between continuous capillaries, fenestrated and sinusoids. The walls of the blood consist of a basal lamina and an endothelium.

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