Explanation The rate at which blood is returned to the heart by veins is the same as that of blood pumped from the heart in the arteries during circulation. In order to prevent the flow of blood in the backward direction in the veins, there are structures called venous valves. Venous valves are the two flap-like structures in the veins. They act as barriers and ensure unidirectional blood flow...

6th Edition

ISBN: 9780134156415

Author: Elaine N. Marieb, Katja N. Hoehn

Publisher: PEARSON

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Question

Chapter 18.4, Problem 5CYU

Summary Introduction

To review:

The function and formation of venous valves.

Introduction:

Veins are the blood vessels that carry blood towards the heart from various capillary beds. The capillaries unite to form venules and venules join to form veins. The diameter successively increases from the venules to the larger veins. In the veins of limbs, where gravity opposes the upward flow of blood, venous valves are most abundantly found.

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Chapter 18.3, Problem 4CYU

Chapter 18.4, Problem 6CYU

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Chapter 18 Solutions

Anatomy & Physiology (6th Edition)

Ch. 18.1 - Which branch of the autonomic nervous system...Ch. 18.1 - When vascular smooth muscle contracts, what...Ch. 18.2 - Name the type of artery that matches each...Ch. 18.3 - Prob. 4CYU Ch. 18.4 - Prob. 5CYU Ch. 18.4 - In the systemic circuit, which contains more...Ch. 18.5 - Prob. 7CYU Ch. 18.6 - List three factors that determine resistance in a...Ch. 18.6 - Suppose vasoconstriction decreases the diameter of...Ch. 18.7 - Prob. 10CYU

Ch. 18.8 - Prob. 11CYU Ch. 18.8 - The kidneys play an important role in maintaining...Ch. 18.8 - Your neighbor, Bob, calls you because he thinks he...Ch. 18.8 - Prob. 14CYU Ch. 18.9 - Suppose you are in a bicycle race. What happens to...Ch. 18.9 - If many arterioles in your body dilated at once,...Ch. 18.10 - Prob. 17CYU Ch. 18.11 - Prob. 18CYU Ch. 18.11 - Prob. 19CYU Ch. 18.11 - Prob. 20CYU Ch. 18.11 - You are assessing the circulation in the leg of a...Ch. 18.11 - In what important way does the area drained by the...Ch. 18.11 - Prob. 23CYU Ch. 18.11 - Prob. 24CYU Ch. 18.11 - Name the leg veins that often become varicosed.Ch. 18 - Which statement does not accurately describe...Ch. 18 - Smooth muscle in the blood vessel wall (a) is...Ch. 18 - Peripheral resistance (a) is inversely...Ch. 18 - Which of the following can lead to decreased...Ch. 18 - Prob. 5MC Ch. 18 - Prob. 6MC Ch. 18 - The structure of a capillary wall differs from...Ch. 18 - Prob. 8MC Ch. 18 - The myocardium receives its blood supply directly...Ch. 18 - Blood flow in the capillaries is steady despite...Ch. 18 - Prob. 11MC Ch. 18 - Tracing the blood from the heart to the right...Ch. 18 - Prob. 13MC Ch. 18 - Prob. 14MC Ch. 18 - How is the anatomy of capillaries and capillary...Ch. 18 - Prob. 16SAQ Ch. 18 - Write an equation showing the relationship between...Ch. 18 - Prob. 18SAQ Ch. 18 - Describe the neural mechanisms responsible for...Ch. 18 - Explain the reasons for the observed changes in...Ch. 18 - Prob. 21SAQ Ch. 18 - Prob. 22SAQ Ch. 18 - How are nutrients, wastes, and respiratory gases...Ch. 18 - Prob. 24SAQ Ch. 18 - Physiologists often consider capillaries and...Ch. 18 - Mr. Hutchinson, another middle-aged victim of the...Ch. 18 - Mr. Hutchinson, another middle-aged victim of the...Ch. 18 - Mr. Hutchinson, another middle-aged victim of the...

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Solution Summary: The author explains the function and formation of venous valves in the veins of the thoracic and abdominal cavity.

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