Loose Leaf For Integrated Principles Of Zoology
18th Edition
ISBN: 9781260411140
Author: Cleveland P Hickman Jr. Emeritus, Susan L. Keen, David J Eisenhour Professor PhD, Allan Larson, Helen I'Anson Associate Professor of Biology
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 31, Problem 7RQ
Explain the origin and conduction of the excitation that leads to a heart contraction. Why is the vertebrate heart said to be myogenic? If the heart is myogenic, how do you account for alterations in rate of the heartbeat?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Left Atrium
Right Atrium
Left Ventricle
Right Ventricle
b) On the diagram of the heart above, use arrows to show the pathway of blood
through the heart and its associated vessels.
c) Use a blue colored pencil to shade in all regions of the heart that carry
deoxygenated blood and a red colored pencil to shade in the regions that carry
oxygenated blood.
Conclusion:
Why is the gap junctions between heart muscle cells play a relevant role in producing a regular heartbeat?
Which of the following statements best describes the differences in the regulation of cardiac and skeletal muscle contraction?
The amount of contractile force actively generated by muscle cells is increased by stretch in skeletal muscle and decreased by stretch in cardiac muscle.
Cardiac muscle is stimulated by motor neurons and skeletal muscle by neurones from the autonomic nervous system.
Skeletal muscle contractile force is augmented by increasing the firing frequency of action potentials whereas cardiac muscle contractile force is enhanced by noradrenaline increasing calcium influx through ion channels.
Ryanodine receptors in skeletal muscle are opened by a mechanism that requires calcium influx whereas in cardiac muscle membrane depolarisation alone without calcium influx is sufficient to open ryanodine receptors.
Chapter 31 Solutions
Loose Leaf For Integrated Principles Of Zoology
Ch. 31 - Name the chief intracellular electrolytes and the...Ch. 31 - What is the fate of spent erythrocytes in the...Ch. 31 - Prob. 3RQCh. 31 - Two distinctly different styles of circulatory...Ch. 31 - Place the following in correct order to describe...Ch. 31 - Trace the flow of blood through a mammalian heart,...Ch. 31 - Explain the origin and conduction of the...Ch. 31 - Define the terms systole and diastole. Distinguish...Ch. 31 - Prob. 9RQCh. 31 - Prob. 10RQ
Ch. 31 - Prob. 11RQCh. 31 - Describe an advantage of a fishs gills for...Ch. 31 - Describe the tracheal system of insects. What is...Ch. 31 - Trace the route of inspired air in humans from the...Ch. 31 - Prob. 15RQCh. 31 - How does a frog ventilate its lungs? Contrast an...Ch. 31 - What is the role of carbon dioxide in the control...Ch. 31 - Prob. 18RQCh. 31 - Prob. 19RQCh. 31 - The ability of hemoglobin to bind oxygen decreases...Ch. 31 - At high altitudes, the partial pressure of oxygen...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
- The pressure in the aorta changes throughout the cardiac cycle. During systole, as the heart contracts, the outflux of blood into the aorta causes an increase in pressure, whereas during diastole the pressure decreases as the heart relaxes. A simple model for the aortic pressure waveform is given by the Windkessel effect described by the image below. In this model, the heart is considered a pressure generating pump which is directly connected to an elastic compartment (the aorta), which in turn is connected to a rigid set of peripheral vessels (the hose of the firefighter). 5 Pump Heart Air Windkessel Elastic arteries In order to find the aortic pressure waveform from the Windkessel model, a mass balance formulation around the aorta must be formulated. Coming into the aorta from the heart we have the flowrate Q(t). According to conservation of mass, this inflow rate Q(t) must be equal to the outflow rate into the peripheral vessels and the change in volume of the aorta. To find these…arrow_forwardDiagram electrical conduction of the heart and discuss each component (SA node, AV node, etc). How does this dictate the fluidity of heart contraction? Why does the SA always start the conduction? What is the inherent rate of depolarization of the SA node (this means that if the nervous system was shut off what would resting bpm be)? If it is damaged what happens to the electrical conduction system?arrow_forwardWhat is the consequence of the prolonged plateau of depolarization in ventricular myocytes? a-it causes ventricular myocytes to contract for a longer time, allowing the ventricles time to empty b-it gives additional time for the atria to contract, filling the ventricles more completely c-it causes repolarization to be delayed which slows heart rate d-it allows the ventricles a moment to rest before completing contractionarrow_forward
- Which statement about activation of heart muscle cells is TRUE? A when a person is resting only a few small motor units in each ventricle are activated in each heartbeat B all of the muscle cells in the ventricles depolarize and contract together because they are connected by gap junctions C motor neurons must synapse with all of the muscle cells in the ventricles at the same time or fibrillation will occur D all of the heart muscle cells have unstable resting membrane potenitals and slowly depolarize to threshold at the same ratearrow_forwardWe analyzed the difference between the action potential of a cardiac contractile cell and an action potential in a neuron. Describe the physiological mechanisms behind the primary difference in the shape of these two action potentials. Why is this feature important to the normal workings of the heart?arrow_forwardDescribe the action potential of an autorhythmic cell in the heart.a) Indicate how the opening and closing of each ion channel affects the membrane potential of the cell.b) Provide one similarity between the action potential of an autorhythmic cell and the action potential of a neuron.c) Provide one difference between the action potential of an autorhythmic cell and the action potential of a neuron.arrow_forward
- The mammalian heart can beat without input from the brain. True Or false?arrow_forwardDescribe why your heart rate increases with exercise. What would happen if your heart did not beat faster with exercise?arrow_forwardAn artificial heart works in closed loop by varying its pumping rate according to changes in signals from the recipient's nervous system. For feedback compensation design it is important to know the heart's open-loop transfer function. To identify this transfer function, an artificial heart is implanted in a calf while the main parts of the original heart are left in place. Then the atrial pumping rate in the original heart is measured while step input changes are effected on the artificial heart. It has been found that. in general, the obtained response closely resembles that of a second-order system. In one such experiment it was found that the step response has a %OS = 30% and a time of first peak 7, 127 sec (Nakamura, 2002). Find the corresponding transfer function. Aside from the corresponding transfer function, determine the following as well: delay time, rise time, settling time and steady state error if input is a step response. CO Marrow_forward
- A heartbeat starts when autorhythmic cells in the 1 [ Select ] (located in the right atrium) create an action potential (electric signal). From there, the signal passes along the internodal pathway to the 2 [ Select] causing the atria to contract. After a slight pause, the signal travels to the 3 [ Select ] , which divides into left and right bundle branches and carries the signal down through the 4 [ Select ] to the apex of the heart. At that point, specialized 5 [ Select ] carry the signal to individual cardiac muscle cells and the 6 [ Select ] contract.arrow_forwardDoes the human heart spend more time in diastole or more time in systole (assume a heart rate of 72 beats per minute)? Of what benefit is this?arrow_forwardDefine death in physiological terms. We know that when the human heart stops beating, it can be started again artificially. And the subject lives. If the heart does not restart, the O2 supply is cut off, the brain cells die, but what does lack of O2 cause? Include mechanisms.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Human Biology (MindTap Course List)BiologyISBN:9781305112100Author:Cecie Starr, Beverly McMillanPublisher:Cengage Learning
Human Physiology: From Cells to Systems (MindTap ...BiologyISBN:9781285866932Author:Lauralee SherwoodPublisher:Cengage Learning
Human Biology (MindTap Course List)
Biology
ISBN:9781305112100
Author:Cecie Starr, Beverly McMillan
Publisher:Cengage Learning
Human Physiology: From Cells to Systems (MindTap ...
Biology
ISBN:9781285866932
Author:Lauralee Sherwood
Publisher:Cengage Learning
The Cardiovascular System: An Overview; Author: Strong Medicine;https://www.youtube.com/watch?v=Wu18mpI_62s;License: Standard youtube license