EBK HUMAN PHYSIOLOGY
8th Edition
ISBN: 9780134704227
Author: Silverthorn
Publisher: YUZU
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Chapter 15, Problem 28RQ
Summary Introduction
To determine: The mechanism of action of atropine during sympathetic and parasympathetic neuron intervention in the frog’s heart.
Introduction: Activity of the circulatory system is greatly affected by different signaling bio-chemicals. Each molecule has its own mode of action of the different parts of the circulatory system. The concentration of these
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a) A consequence of the Frank-Starling law of the heart is that the outputs of the right and left ventricles match. Explain why this is important and how this match is made.b) The excitation-contraction matching mechanism within the heart muscle is different from that of the skeletal muscle. How might these differences be related to the difference between action potentials in cardiac muscle and skeletal muscle?
Consider the ventricular cardiomyocyte action potential shown below:
a) Which phase of the cardiac myocyte action potential would be most significantly affected by the L-type calcium channel blocker nifedipine?
b) Draw the predicted effects of nifedipine on the cardiac myocyte action potential.
When given an image of a cardiac contractile cell, such as the one below, describe
the steps that occur during excitation-contraction coupling (the "before step 1" step
show with the squiggly red arrow below), contraction (steps 1-6 below) AND
relaxation (steps 7-10 belowl). Be sure to fully describe the role of Ca¹² ATPase and
Na+Ca+2 exchanger (NCX) in steps 9 and 101
ECF
ICF
SR
Ca2+
RyR
Cat sparks
Ca signal
Contraction
Ca
channel
T-tubule
2 K
ATP
ATP
3 Na
Ca²+
Sarcoplasmic reticulum
Cat stores
(SR)
3 Nat Ca
NCX
Relaxation
Ca2+
Actin
Myosin
Chapter 15 Solutions
EBK HUMAN PHYSIOLOGY
Ch. 15.2 - Would you expect to find valves in the veins...Ch. 15.2 - Prob. 2CCCh. 15.2 - Who has the higher pulse pressure, someone with...Ch. 15.2 - The formula given for calculating MAP applies to a...Ch. 15.2 - Prob. 5CCCh. 15.3 - Resistance to blood flow is determined primarily...Ch. 15.3 - Prob. 7CCCh. 15.3 - Prob. 8CCCh. 15.3 - Skeletal muscle arterioles have both - and...Ch. 15.4 - Prob. 10CC
Ch. 15.4 - Prob. 11CCCh. 15.5 - Prob. 12CCCh. 15.5 - In the classic movie Jurassic Park, Dr. Ian...Ch. 15.6 - A man with liver disease loses the ability to...Ch. 15.6 - Prob. 15CCCh. 15.7 - Prob. 16CCCh. 15.7 - Malnourished children who have inadequate protein...Ch. 15 - Prob. 1RQCh. 15 - Prob. 2RQCh. 15 - Prob. 3RQCh. 15 - Prob. 4RQCh. 15 - Prob. 5RQCh. 15 - Prob. 6RQCh. 15 - List the factors that aid venous return to the...Ch. 15 - Prob. 8RQCh. 15 - Prob. 9RQCh. 15 - Prob. 10RQCh. 15 - Prob. 11RQCh. 15 - Most systemic arterioles are innervated by the...Ch. 15 - Match each event in the left column with all...Ch. 15 - Which organs receive more than two-thirds of the...Ch. 15 - By looking at the density of capillaries in a...Ch. 15 - Prob. 16RQCh. 15 - Prob. 17RQCh. 15 - Define edema. List some ways in which it can...Ch. 15 - Prob. 19RQCh. 15 - Prob. 20RQCh. 15 - Calcium channel blockers prevent Ca2+ movement...Ch. 15 - Prob. 22RQCh. 15 - Prob. 23RQCh. 15 - Define myogenic autoregulation. What mechanisms...Ch. 15 - Left ventricular failure may be accompanied by...Ch. 15 - Robert is a 52-year-old nonsmoker. He weighs 180...Ch. 15 - The following figure is a schematic representation...Ch. 15 - Prob. 28RQCh. 15 - Draw a reflex map that explains Anthonys vasovagal...Ch. 15 - Prob. 30RQCh. 15 - Prob. 31RQCh. 15 - Prob. 32RQCh. 15 - Prob. 33RQCh. 15 - Prob. 34RQCh. 15 - Prob. 35RQCh. 15 - Prob. 36RQCh. 15 - Prob. 37RQCh. 15 - Prob. 38RQCh. 15 - Prob. 39RQ
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