Explanation Metarterioles are the small vessels connecting arterioles and capillaries or providing blood shortcuts to bypass the capillaries and pass directly into a venule. They have isolated individual muscle cells a short distance apart instead of a continuous tunica media, each forming a precapillary sphincter that surrounds the entrance to one capillary...

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Question

Chapter 21, Problem 21.1.5AYLO

Summary Introduction

To analyze:

The location, structure, and functions of metarterioles and precapillary spincters.

Introduction:

Arteries are defined as the cardiovascular system's afferent vessels, i.e. vessels transporting blood from the heart. Arteries are called the cardiovascular system's resistance vessels as they have a fairly strong, resilient tissue layer that is resistant to high blood pressure within. With about one to three layers of smooth muscle, the smallest resistance arteries are called arterioles. Arterioles seem to have little external tunica. They are the main point of regulate over how much blood is received by an organ or tissue.

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Chapter 21, Problem 21.1.4AYLO

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