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Questions and Answers
What is the equation used to calculate cardiac output?
What is the equation used to calculate cardiac output?
What is the average stroke volume per beat?
What is the average stroke volume per beat?
Which valves are classified as atrioventricular valves?
Which valves are classified as atrioventricular valves?
During which phase do semilunar valves open?
During which phase do semilunar valves open?
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What role do pacemaker cells play in the heart?
What role do pacemaker cells play in the heart?
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What effect do motor neurons from the Sympathetic and Parasympathetic nervous system have on the heart?
What effect do motor neurons from the Sympathetic and Parasympathetic nervous system have on the heart?
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What can the cardiac output increase to during exercise?
What can the cardiac output increase to during exercise?
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What is the primary function of the gap junctions in cardiac muscle cells?
What is the primary function of the gap junctions in cardiac muscle cells?
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What primarily drives the net movement of K+ out of the cell during the repolarization plateau?
What primarily drives the net movement of K+ out of the cell during the repolarization plateau?
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What happens to voltage-gated Ca2+ channels during final repolarization (phase 3)?
What happens to voltage-gated Ca2+ channels during final repolarization (phase 3)?
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During which phase do voltage-gated Na+, K+, and Ca2+ channels close?
During which phase do voltage-gated Na+, K+, and Ca2+ channels close?
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What is the result of the inactivation of voltage-gated Ca2+ channels in phase 3?
What is the result of the inactivation of voltage-gated Ca2+ channels in phase 3?
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How does the net cation efflux via K+ compare to the net cation influx via Ca2+ during the repolarization plateau?
How does the net cation efflux via K+ compare to the net cation influx via Ca2+ during the repolarization plateau?
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What primarily stimulates the opening of voltage-gated Ca2+ channels in the cardiac action potential?
What primarily stimulates the opening of voltage-gated Ca2+ channels in the cardiac action potential?
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What effect does the blockage of K+ leak channels have during repolarization phases?
What effect does the blockage of K+ leak channels have during repolarization phases?
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Why does the electrical gradient influence cation movement during phase 2?
Why does the electrical gradient influence cation movement during phase 2?
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What occurs immediately after the closure of the AV valves during the cardiac cycle?
What occurs immediately after the closure of the AV valves during the cardiac cycle?
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Which heart sound is associated with the closing of the AV valves?
Which heart sound is associated with the closing of the AV valves?
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During diastole, what is the relationship between left ventricular pressure and left atrial pressure?
During diastole, what is the relationship between left ventricular pressure and left atrial pressure?
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What phase follows the depolarization of the atrium indicated by the P wave?
What phase follows the depolarization of the atrium indicated by the P wave?
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What occurs during isovolumetric contraction?
What occurs during isovolumetric contraction?
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What happens during the relaxation of cardiac muscle in the cardiac cycle?
What happens during the relaxation of cardiac muscle in the cardiac cycle?
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Which of the following indicates the beginning of systole?
Which of the following indicates the beginning of systole?
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What marks the end of systole in the cardiac cycle?
What marks the end of systole in the cardiac cycle?
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What is the primary function of the atrial volume receptor reflex?
What is the primary function of the atrial volume receptor reflex?
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In response to decreased blood volume, how does the atrial volume receptor reflex affect renin release?
In response to decreased blood volume, how does the atrial volume receptor reflex affect renin release?
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Which of the following best describes what an electrocardiogram (ECG) measures?
Which of the following best describes what an electrocardiogram (ECG) measures?
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How are ECG leads arranged to provide standard comparisons in heart activity recordings?
How are ECG leads arranged to provide standard comparisons in heart activity recordings?
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What is the main reason for using the same 12 leads in all ECG recordings?
What is the main reason for using the same 12 leads in all ECG recordings?
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What role do baroreceptors play in blood pressure regulation?
What role do baroreceptors play in blood pressure regulation?
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How does the CNS respond to changes in blood pressure detected by baroreceptors?
How does the CNS respond to changes in blood pressure detected by baroreceptors?
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What is the primary function of the baroreceptor reflex?
What is the primary function of the baroreceptor reflex?
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What is the speed of the baroreceptor reflex in regulating blood pressure?
What is the speed of the baroreceptor reflex in regulating blood pressure?
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How does the baroreceptor reflex adapt to long-term changes in blood pressure?
How does the baroreceptor reflex adapt to long-term changes in blood pressure?
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What is the average systolic blood pressure in mmHg?
What is the average systolic blood pressure in mmHg?
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How is pulse pressure calculated?
How is pulse pressure calculated?
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What is the formula for Mean Arterial Pressure (MAP)?
What is the formula for Mean Arterial Pressure (MAP)?
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Which vessel type has the greatest total cross-sectional area?
Which vessel type has the greatest total cross-sectional area?
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What happens to blood flow velocity as total cross-sectional area increases?
What happens to blood flow velocity as total cross-sectional area increases?
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Which variable has the largest impact on vascular resistance?
Which variable has the largest impact on vascular resistance?
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If the radius of one tube is twice that of another tube, how does their resistance compare?
If the radius of one tube is twice that of another tube, how does their resistance compare?
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In systemic circulation, what kind of pressure and resistance is typical?
In systemic circulation, what kind of pressure and resistance is typical?
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Which of the following correctly describes the relationship between surface area and diffusion efficiency?
Which of the following correctly describes the relationship between surface area and diffusion efficiency?
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Study Notes
Physiology (0603302)
- Course: Cardiac Physiology
- Semester: Summer 2023/2024
- Instructor: Dr. Mohammad A. Abedal-Majed
- Institution: The University of Jordan, School of Agriculture
Cardiac Cycle
-
Contraction of cardiac muscle:
- Increased ventricular chamber pressure
- Closing of AV (inlet) valves
- Opening of SL (outlet) valves
-
Relaxation of cardiac muscle:
- Decreased ventricular chamber pressure
- Closing of SL(outlet) valves
- Opening of AV (inlet) valves
Blood Flow
-
Pulmonary Circulation (short):
- Poorly oxygenated blood to lungs
- Right ventricle → pulmonary artery → pulmonary vessels
- Delivery of highly oxygenated blood to the heart
- Pulmonary vessels → pulmonary vein
-
Systemic Circulation (high pressure):
- Highly oxygenated blood to tissues
- Left ventricle → aorta → systemic vessels
- Delivery of poorly oxygenated blood to the heart
- Systemic vessels → vena cava → R atrium
Vascular System
-
Functional components:
- Pump (heart)
- Distributing tubes (arterial system)
- Collecting tubes (venous system)
- Exchange system (capillary beds)
-
Distributing (arterial system):
- Branching of aorta & pulmonary artery
- Progressively smaller vessels (arteries → arterioles → capillaries)
-
Collecting (venous system):
- Empty into vena cava & pulmonary vein
- Joining of smaller vessels (venules → veins)
- Back to the heart via vena cava
-
Exchange (capillary beds):
- Oxygen, glucose, and nutrients pass from blood to cells
- Carbon dioxide, and waste products pass from cells to blood
Cardiac Action Potentials
-
Fast response action potential:
- Rapid depolarization phase
- Influx of Na+ ions
- Brief repolarization
-
Slow response action potential:
- Repolarization plateau phase
- Influx of Ca2+ ions
- Depolarization caused by Ca2+ influx
Cardiac Valves
-
Atrioventricular valves: Control blood flow between atria and ventricles
- Left: mitral valve
- Right: tricuspid valve
- Open during atrial contraction, close during ventricular contraction
-
Semilunar valves: Control blood flow from ventricles into arteries
- Left: aortic valve
- Right: pulmonic valve
- Open during ventricular contraction, close during ventricular relaxation
Heart Valves
-
Atrioventricular (AV): control blood flow between atria and ventricles
- Mitral (Left)
- Tricuspid (Right)
-
Semilunar: control blood exiting ventricles
- Aortic (Left)
- Pulmonary (Right)
Cardiac Cycle
- A contraction phase (systole) and a relaxation phase (diastole).
Blood Pressure
-
Regulation:
- Sympathetic nervous system (↑ heart rate, ↑ contractility, ↑ vasoconstriction) -Parasympathetic nervous system (↓ heart rate,↓ contractility, ↓ vasoconstriction)
-
Blood pressure measurements
- First sound-AV valves close
- Second sound-Semilunar valves close.
- Vascular Resistance and Blood pressure: Pressure driven blood flow, Resistance is inversely correlated with radius(smaller radius = greater resistance).
Baroreceptors and Volume Reflexes
-
Baroreceptor reflex: Detecting changes in blood pressure
- Afferent signals from baroreceptors to the CNS
- CNS then modulates sympathetic and parasympathetic activity to return blood pressure to normal
-
Atrial volume receptor reflex: Detecting changes in blood volume
- Detecting changes in atrial stretch
- CNS then modulates sympathetic and parasympathetic activity to maintain blood volume
- Role of renin-angiotensin-aldosterone system (RAAS)
Clinical Applications
- ECG: Graphical tracing of cardiac electrical potentials. Uses 12 leads to record data from various locations on the body. Used clinically to detect heart disease.
- Blood viscosity: Blood becomes more viscous in cases of polycythemia, and less viscous in anemia.
- Blood pressure measurements: Detecting blood pressure changes in arteries via Korotkoff sounds.
Additional Information (Not fully organized):
- Cardiac output = stroke volume x heart rate (CO = SV * HR)
- Resting CO = ~5 Liters/min, Exercising CO = 20 - 25 Liters/min
- Various components of heart, lungs, and vascular system are associated with blood flow and pressure regulation
- Multiple diagrams describe circulation, blood flow, and pressure differences from the heart, and through large and small blood vessels such as arteries, arterioles, capillaries, venules, and veins throughout the body.
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Description
This quiz covers essential concepts of cardiac physiology, including cardiac output, stroke volume, and the roles of heart valves and pacemaker cells. Test your knowledge on how the nervous system influences heart function and the mechanics of cardiac muscle cells. Perfect for students of human physiology or medical professionals seeking to refresh their understanding.
