Explanation Sinoatrial node is composed of the specialized cardiac muscles, which are located near the region of the vena cava (superior) underneath the inner layers of the pericardium. The sinoatrial node initiates around eighty impulses in a minute. The generated impulses are transported from the atrium. The cardiac skeleton is an insulating body. The impulses cannot be passed through it. The impulse can travel only through the atrioventricular node to the ventricular region...

4th Edition

ISBN: 9781265061173

Author: McKinley

Publisher: MCG CUSTOM

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Question

Chapter 19.5, Problem 20WDYL

Summary Introduction

To describe:

The SA node as the “pacemaker of heart”.

Introduction:

The association of the organized cardiac muscle cells, which are specialized in their functioning, is called cardiac conduction system. The cardiac muscles generally contract, but the muscles of cardiac conduction system perform the initiation and distribution of the impulses across the myocardium.

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Chapter 19.4, Problem 19WDYL

Chapter 19.5, Problem 21WDYL

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Chapter 19 Solutions

ANATOMY & PHYSIOLOGY 4/E PAC 1 SEMESTER

Ch. 19.1 - Prob. 1WDYL Ch. 19.1 - Prob. 2WDYL Ch. 19.1 - Prob. 3WDYL Ch. 19.1 - Prob. 4WDYL Ch. 19.1 - Prob. 5WDYL Ch. 19.2 - What is the bony structure that protects both the...Ch. 19.2 - Prob. 7WDYL Ch. 19.2 - Prob. 8WDYL Ch. 19.3 - Prob. 9WDYL Ch. 19.3 - Prob. 10WDYL

Ch. 19.3 - Prob. 11WDYL Ch. 19.3 - Prob. 12WDYL Ch. 19.3 - Prob. 13WDYL Ch. 19.3 - Prob. 14WDYL Ch. 19.3 - Prob. 15WDYL Ch. 19.3 - Prob. 16WDYL Ch. 19.3 - What areas of the heart are deprived of blood when...Ch. 19.3 - Prob. 18WDYL Ch. 19.4 - Prob. 19WDYL Ch. 19.5 - Prob. 20WDYL Ch. 19.5 - Which autonomic division is associated with the...Ch. 19.6 - Prob. 22WDYL Ch. 19.6 - What is autorhythmicity? Describe how nodal cells...Ch. 19.6 - What is the path of an action potential through...Ch. 19.6 - What anatomic features slow the conduction rate of...Ch. 19.7 - In which direction does Ca2+ move in response to...Ch. 19.7 - What three electrical events occur at the...Ch. 19.7 - What is the significance of the extended...Ch. 19.7 - What events in the heart are indicated by each of...Ch. 19.8 - Pressure changes that occur during the cardiac...Ch. 19.8 - What is occurring during ventricular ejection?Ch. 19.8 - Prob. 32WDYL Ch. 19.8 - Define end-diastolic volume, end-systolic volume,...Ch. 19.9 - What are the two factors that determine cardiac...Ch. 19.9 - What is the cardiac output at rest and during...Ch. 19.9 - Prob. 36WDYL Ch. 19.9 - Describe the atrial reflex, which involves...Ch. 19.9 - Prob. 38WDYL Ch. 19.9 - Prob. 39WDYL Ch. 19.10 - What would be the path of blood flow through the...Ch. 19 - Which of the following is the correct circulatory...Ch. 19 - The pericardial cavity is located between the a....Ch. 19 - How is blood prevented from backflowing from the...Ch. 19 - ____ 4. Venous blood draining from the heart wall...Ch. 19 - _____ 5. Calcium channels in the nodal cells...Ch. 19 - ____6. Action potentials are spread rapidly...Ch. 19 - Why is it necessary to stimulate papillary muscles...Ch. 19 - ____ 8. Preload is a measure of a. stretch of...Ch. 19 - ____ 9. All of the following occur when the...Ch. 19 - ____10. What occurs during the atrial reflex? a....Ch. 19 - Prob. 11DYKB Ch. 19 - Compare the structure, location, and function of...Ch. 19 - Prob. 13DYKB Ch. 19 - Explain why the walls of the atria are thinner...Ch. 19 - Describe the structure and function of...Ch. 19 - Explain the general location and function of...Ch. 19 - Describe the functional differences in the effects...Ch. 19 - Prob. 18DYKB Ch. 19 - List the five events of the cardiac cycle, and...Ch. 19 - Define cardiac output, and explain how it is...Ch. 19 - A young man was doing some vigorous exercise when...Ch. 19 - A young man was doing some vigorous exercise when...Ch. 19 - Prob. 3CAL Ch. 19 - Prob. 4CAL Ch. 19 - During surgery, the right vagus nerve was...Ch. 19 - Prob. 1CSL Ch. 19 - Prob. 2CSL Ch. 19 - Your grandfather was told that his SA node...

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Solution Summary: The author describes the SA node as the "pacemaker of heart".

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