Questions and Answers
The apex of the heart is __________.
inferior
What surface groove separates the right and left ventricles?
The pulmonary circuit involves blood flow from the heart to the:
The vessels that deliver oxygen to the tissues of the body are part of the __________.
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In which chamber would the loss of function be most damaging to survival?
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Which of the following vessels carries oxygenated blood?
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Blood from the systemic circuit returns to the heart via the __________.
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Which hormone decreases cardiac output by decreasing blood volume and preload?
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What two values are needed in order to calculate cardiac output (CO) for a ventricle?
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What largely determines preload?
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Afterload is described as:
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Which of the following happens immediately after the P wave?
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The aortic valve closes when __________.
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During what phase does blood flow from the ventricles into the pulmonary trunk and aorta?
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The P wave on an electrocardiogram (ECG) represents the depolarization of cells in the:
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What valve prevents the backflow of blood from the right ventricle into the right atrium?
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What vessel delivers oxygenated blood to systemic capillaries for gas exchange?
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What vessel(s) deliver oxygenated blood to the left atrium?
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Autorhythmicity in the heart is the responsibility of:
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What characteristic differentiates cardiac muscle cells from skeletal muscle cells?
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Certain drugs used to treat dysrhythmias, called local anesthetics, work by blocking voltage gated sodium ion channels and slowing the entry of sodium ions into the cell during an action potential. What effects would you see?
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Unlike skeletal muscle action potentials, cardiac muscle action potentials __________.
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What normally serves as the pacemaker of the entire heart?
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A patient has a heart rate of 70 beats per minute, an EDV of 110 ml, and an ESV of 70 ml. What is the patient's cardiac output?
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Study Notes
Heart Anatomy and Physiology
- The apex of the heart is the inferior tip, pointing toward the left side.
- The interventricular sulcus separates the right and left ventricles.
Blood Circulation
- The pulmonary circuit involves blood flow from the heart to the lungs.
- The systemic circuit delivers oxygen to body tissues, connecting the heart to systemic tissues.
Cardiac Function and Injury
- Loss of function in the left ventricle due to myocardial infarction (MI) is most damaging for survival, as it sends blood to the body.
- Blood from the systemic circuit returns to the heart via the superior and inferior venae cavae.
Cardiac Regulation
- Atrial natriuretic peptide (ANP) decreases cardiac output by reducing blood volume and preload.
- Cardiac output (CO) is calculated using stroke volume (SV) and heart rate (HR).
- Preload largely depends on end-diastolic volume (EDV).
Cardiac Phases and Action Potentials
- After the P wave on an ECG, the atria contract, allowing for proper ventricular filling.
- The aortic valve closes when left ventricular pressure falls below aortic pressure to prevent backflow.
Valves and Blood Flow
- Blood flows from the ventricles into the pulmonary trunk and aorta during the ventricular ejection phase.
- The tricuspid valve prevents backflow from the right ventricle to the right atrium.
- The aorta delivers oxygenated blood to systemic capillaries.
Vascular Connections
- Oxygenated blood returns to the left atrium via the pulmonary veins.
Cardiac Cells and Pacemaking
- Cardiac pacemaker cells are responsible for the heart's autorhythmicity.
- Intercalated discs differentiate cardiac muscle cells from skeletal muscle cells.
Pharmacological Effects
- Local anesthetics block sodium ion channels, decreasing cell depolarization and affecting cardiac action potentials.
- Cardiac muscle action potentials involve calcium voltage-gated channels, leading to a plateau phase.
Heart Rate and Cardiac Output Calculation
- The sinoatrial (SA) node normally serves as the pacemaker for the entire heart.
- A patient with a heart rate of 70 beats per minute, an EDV of 110 ml, and an ESV of 70 ml has a cardiac output of 2.8 L/minute, calculated using SV = EDV - ESV and CO = SV × HR.
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Description
Test your knowledge on the anatomy and physiology of the heart. This quiz covers topics such as blood circulation mechanics, cardiac function, and the regulation of heart action. Dive into the details of how the heart operates and its significance in the human body.
