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WorksheetsMission 5 The CVS study guide
Total questions: 127
Worksheet time: 1hrs 4mins
What is the name of the heart's natural pacemaker?
Atrioventricular (AV) Node
Bundle of His
Sinoatrial (SA) Node
Purkinje Fibers
Where is the sinoatrial (SA) node located?
Right Atrium
Left Atrium
Right Ventricle
Left Ventricle
What is the function of the atrioventricular (AV) node?
To generate the initial electrical impulse
To delay the electrical signal slightly, allowing the ventricles to fill
To spread the electrical impulse to the Purkinje fibers
To regulate heart rate during exercise
Which structure transmits signals from the AV node to the ventricles?
Purkinje Fibers
Right and Left Bundle Branches
Bundle of His
Sinoatrial (SA) Node
Where are the Purkinje fibers located?
Septum of the heart
Walls of the ventricles
Atria of the heart
Aorta
What is the final step in the path of the electrical impulse through the heart?
Signal reaches the AV node.
Signal reaches the Purkinje fibers, causing ventricular contraction.
Signal travels down the Bundle of His.
Signal originates in the SA node.
What happens if the SA node fails to function?
The heart stops beating entirely.
The AV node takes over as the pacemaker.
The Purkinje fibers immediately generate impulses.
The heart rate increases significantly.
What is the approximate heart rate generated by the AV node when it acts as the pacemaker?
20-40 beats per minute
40-60 beats per minute
60-80 beats per minute
80-100 beats per minute
If both the SA and AV nodes fail, which structures can generate electrical impulses?
Ventricular Pacemakers (Bundle of His or Purkinje Fibers)
Coronary arteries
Heart valves
Pericardium
What is the term for a slower-than-normal heart rate?
Tachycardia
Bradycardia
Arrhythmia
Fibrillation
What can cause decreased cardiac output when the SA node fails?
Increased blood pressure
The heart may not pump blood as efficiently
Excessive physical activity
High blood sugar levels
What are irregular heart rhythms called?
Bradycardia
Tachycardia
Arrhythmias
Heart murmurs
Which of the following is NOT a potential treatment option for SA node failure?
Medications
Lifestyle changes, such as diet and exercise
Pacemaker
All of the above are potential treatment options.
The right and left bundle branches carry the electrical impulse:
Upwards towards the atria
Down both sides of the heart's septum to the ventricles
Only to the right ventricle
Only to the left ventricle
The function of the heart's conduction system is to:
Produce red blood cells
Filter waste products from the blood
Ensure the heart pumps blood effectively
Regulate body temperature
The electrical impulse in the heart originates in the:
AV node
Bundle of His
SA node
Purkinje fibers
Which of the following is a possible consequence of SA node failure?
Increased heart rate
Fatigue
High blood pressure
Improved blood circulation
A pacemaker is:
A medication to regulate heart rate
A surgical procedure to repair the heart
An artificial device implanted to maintain a regular heart rhythm
A type of exercise to strengthen the heart
The AV node is located:
In the left atrium
At the junction between the atria and ventricles
In the right ventricle
Below the Purkinje fibers
What is the primary function of the Purkinje fibers?
Generate the initial electrical impulse
Delay the electrical signal
Transmit signals from the AV node
Spread the electrical impulse, causing ventricular contraction
Which chambers of the heart receive blood from the body and lungs?
Ventricles
Atria
Septum
Aorta
What are the lower chambers of the heart called?
Atria
Ventricles
Myocardium
Pericardium
Which valve separates the right atrium from the right ventricle?
Mitral valve
Pulmonary valve
Aortic valve
Tricuspid valve
What valve prevents backflow of blood from the left ventricle into the left atrium?
Tricuspid valve
Pulmonary valve
Aortic valve
Mitral valve
Which valve is located between the right ventricle and the pulmonary artery?
Mitral valve
Pulmonary valve
Aortic valve
Tricuspid valve
What is the name of the valve that separates the left ventricle from the aorta?
Mitral valve
Pulmonary valve
Aortic valve
Tricuspid valve
What is the main artery that carries oxygenated blood away from the heart to the body?
Pulmonary artery
Vena cava
Pulmonary vein
Aorta
Which blood vessels carry deoxygenated blood back to the heart from the body?
Pulmonary arteries
Vena cava
Pulmonary veins
Aorta
What are the blood vessels that carry oxygenated blood from the lungs to the heart?
Pulmonary arteries
Vena cava
Pulmonary veins
Aorta
What is the function of the papillary muscles?
To contract the atria
To open the semilunar valves
To prevent the atrioventricular valves from prolapsing
To regulate the heart rate
Which layer of the heart wall is the muscular layer responsible for contractions?
Epicardium
Myocardium
Endocardium
Pericardium
What is the inner lining of the heart chambers called?
Epicardium
Myocardium
Endocardium
Pericardium
What is the term for the contraction phase of the cardiac cycle, when the heart ejects blood?
Systole
Diastole
Repolarization
Depolarization
What is the term for the relaxation phase of the cardiac cycle, when the heart fills with blood?
Systole
Diastole
Repolarization
Depolarization
Why is the left ventricle thicker than the right ventricle?
It receives more blood from the atria.
It pumps blood against higher resistance to the entire body.
It has a slower heart rate.
It contains more valves.
What happens during atrial systole?
The atria relax and fill with blood.
The ventricles contract and eject blood.
The atria contract and push blood into the ventricles.
The semilunar valves close.
What occurs during ventricular systole?
The ventricles relax and fill with blood.
The atria contract and push blood into the ventricles.
The ventricles contract and eject blood through the semilunar valves.
The atrioventricular valves open.
What is the volume of blood pumped by the heart per minute called?
Stroke volume
Ejection fraction
Cardiac output
Pulse pressure
How is cardiac output calculated?
Heart rate x stroke volume
Stroke volume / heart rate
End-diastolic volume - end-systolic volume
Systolic pressure - diastolic pressure
What is stroke volume?
The amount of blood remaining in the ventricle after contraction
The percentage of blood ejected from the ventricle with each beat
The volume of blood ejected from the ventricle with each heartbeat
The difference between systolic and diastolic blood pressure
What is the ejection fraction?
The volume of blood pumped per minute
The amount of blood remaining in the ventricle after contraction
The percentage of end-diastolic volume ejected with each heartbeat
The difference between systolic and diastolic blood pressure
What is cardiac reserve?
The amount of blood stored in the heart
The minimum amount of blood the heart needs to pump
The difference between resting cardiac output and maximum cardiac output
The average blood pressure during exercise
What does pulse pressure represent?
The average blood pressure in the arteries
The force of blood against the artery walls
The difference between systolic and diastolic blood pressure
The heart rate during exercise
What is the heart's natural pacemaker?
Atrioventricular (AV) node
Bundle of His
sinoatrial (SA) node
Purkinje fibers
Where is the sinoatrial (SA) node located?
Right atrium
Left atrium
Right ventricle
Left ventricle
What is the function of the atrioventricular (AV) node?
To generate the initial electrical impulse
To delay the electrical signal, allowing the ventricles to fill
To spread the electrical impulse to the Purkinje fibers
To regulate heart rate during exercise
What structure transmits the electrical signal from the AV node to the ventricles?
Purkinje fibers
Right and left bundle branches
Bundle of His
Sinoatrial (SA) node
What is the role of the Purkinje fibers?
To generate the initial electrical impulse
To delay the electrical signal
To transmit signals from the AV node
To rapidly spread the electrical impulse throughout the ventricles
What happens if the SA node fails to function?
The heart stops beating entirely.
The AV node takes over as the pacemaker.
The Purkinje fibers immediately generate impulses.
The heart rate increases significantly.
What happens if the SA node fails to function?
The heart stops beating entirely.
The AV node takes over as the pacemaker.
The Purkinje fibers immediately generate impulses.
The heart rate increases significantly.
What is the approximate heart rate generated by the AV node when it acts as the pacemaker?
20-40 beats per minute
40-60 beats per minute
60-80 beats per minute
80-100 beats per minute
If both the SA and AV nodes fail, what structures can generate electrical impulses?
Ventricular pacemakers (Bundle of His or Purkinje fibers)
Coronary arteries
Heart valves
Pericardium
What is the term for a slower-than-normal heart rate?
Tachycardia
Bradycardia
Arrhythmia
Fibrillation
What are irregular heart rhythms called?
Bradycardia
Tachycardia
Arrhythmias
Heart murmurs
Which of the following is NOT a typical treatment option for SA node failure?
Medications
Lifestyle changes, such as diet and exercise
Pacemaker
All of the above are potential treatment options.
The right and left bundle branches carry the electrical impulse:
Upwards towards the atria
Down both sides of the heart's septum to the ventricles
Only to the right ventricle
Only to the left ventricle
What is the primary function of the heart's conduction system?
Produce red blood cells
Filter waste products from the blood
Ensure the heart pumps blood effectively
Regulate body temperature
Where does the electrical impulse in the heart originate?
AV node
Bundle of His
SA node
Purkinje fibers
Which of the following is a potential consequence of SA node failure?
Increased heart rate
Fatigue
High blood pressure
Improved blood circulation
What is a pacemaker?
A medication to regulate heart rate
A surgical procedure to repair the heart
An implanted device to maintain a regular heart rhythm
A type of exercise to strengthen the heart
Where is the AV node located?
In the left atrium
At the junction of the atria and ventricles
In the right ventricle
Below the Purkinje fibers
What is the correct pathway of blood flow through the right side of the heart?
Pulmonary veins → Right atrium → Tricuspid valve → Right ventricle → Pulmonary valve → Pulmonary arteries → Lungs
Vena cava → Right atrium → Tricuspid valve → Right ventricle → Pulmonary valve → Pulmonary arteries → Lungs
Aorta → Right atrium → Tricuspid valve → Right ventricle → Pulmonary valve → Pulmonary arteries → Lungs
Pulmonary arteries → Right atrium → Tricuspid valve → Right ventricle → Pulmonary valve → Vena cava → Lungs
What is the correct order of blood flow through the left side of the heart?
Aorta → Left atrium → Mitral valve → Left ventricle → Aortic valve → Pulmonary veins → Body
Vena cava → Left atrium → Mitral valve → Left ventricle → Aortic valve → Aorta → Body
Pulmonary veins → Left atrium → Mitral valve → Left ventricle → Aortic valve → Aorta → Body
Pulmonary arteries → Left atrium → Mitral valve → Left ventricle → Aortic valve → Aorta → Lungs
Which of the following describes cardiac muscle tissue?
Non-striated, voluntary
Striated, involuntary
Non-striated, involuntary
Striated, voluntary
What are intercalated discs?
Structures that separate cardiac muscle cells
Specialized junctions that allow for rapid electrical signal transmission between cardiac muscle cells
Nerve endings that control the heart rate
Blood vessels that supply oxygen to the heart muscle
Why does cardiac muscle have a long refractory period?
To allow for continuous contraction
To increase the heart rate
To prevent sustained contraction (tetany) and ensure proper filling of the heart chambers
To decrease the force of contraction
What does the P wave on an electrocardiogram represent?
Ventricular depolarization
Atrial depolarization
Ventricular repolarization
Atrial repolarization
What does the QRS complex on an electrocardiogram represent?
Atrial depolarization
Ventricular depolarization
Ventricular repolarization
Atrial repolarization
What does the T wave on an electrocardiogram represent?
Atrial depolarization
Ventricular depolarization
Ventricular repolarization
Atrial repolarization
Where are baroreceptors located?
In the brain
In the carotid sinuses and aortic arch
In the heart muscle
In the blood vessels of the limbs
What is the function of baroreceptors?
To regulate heart rate
To control blood clotting
To monitor blood pressure changes
To transport oxygen in the blood
What is the function of the hepatic portal vein?
To carry oxygenated blood to the liver
To transport nutrient-rich blood from the digestive organs to the liver
To drain blood from the lower extremities
To carry blood from the liver to the heart
Which arteries branch off the aortic arch?
Pulmonary arteries, coronary arteries
Carotid arteries, femoral arteries
Brachiocephalic artery, left common carotid artery, left subclavian artery
Renal arteries, hepatic artery
Which factor has the greatest influence on blood flow?
Blood viscosity
Vessel length
Vessel radius
Blood pressure
How does increased blood viscosity affect blood flow?
Decreases blood flow
Increases blood flow
Has no effect on blood flow
Increases blood pressure
What is hydrostatic pressure?
The pressure exerted by proteins in the blood
The pressure that forces fluid out of the capillaries
The pressure that pulls fluid back into the capillaries
The pressure in the veins
What is colloid osmotic (oncotic) pressure?
The pressure exerted by proteins in the blood that pulls fluid back into the capillaries
The pressure that forces fluid out of the capillaries
The pressure in the arteries
The pressure in the veins
Which structure serves as the heart's primary pacemaker?
AV
Bundle of
SA Node
Purkinje Fibers
What is the function of the AV node in the cardiac conduction system?
Initiate electrical signals
Distribute signals to the ventricles
Delay impulses to allow ventricular filling
Ensure coordinated ventricular contraction.
If both the SA and AV nodes fail, what maintains the heart rhythm?
Bundle of His
Purkinje Fibers
Ventricular pacemakers
The heart stops beating
Which heart chambers receive blood from the body and lungs?
Ventricles
Atria
Septum
Aorta
What is the name of the valve located between the right atrium and right ventricle?
Tricuspid valve
Mitral valve
Pulmonary valve
Aortic valve
Which valve prevents blood from flowing back into the left ventricle?
Pulmonary valve
Tricuspid valve
Mitral valve
Aortic valve
What is the function of the papillary muscles?
Contract the ventricles
Open the AV valves
Prevent AV valve prolapse during ventricular contraction
Regulate heart rate
Which layer of the heart wall is responsible for the pumping action?
Epicardium
Myocardium
Endocardium
Pericardium
What is the term for the contraction phase of the cardiac cycle?
Systole
Diastole
Repolarization
Depolarization
During which phase of the cardiac cycle do the ventricles fill with blood?
Systole
Diastole
Atrial contraction
Isovolumetric relaxation
Why is the left ventricle thicker than the right ventricle?
It receives more blood.
It pumps blood against higher resistance in systemic circulation
It contracts more frequently.
It has a larger volume.
What occurs during atrial systole?
Ventricles contract.
Atria relax.
Atria contract, pushing blood into ventricles
Ventricles fill with blood.
What is the definition of cardiac output (CO)?
Blood ejected per beat
Heart rate
Stroke volume
Volume of blood pumped per minute
How is stroke volume (SV) calculated?
CO × Heart Rate
EDV - ESV
(SV ÷ EDV) × 100
Systolic pressure - Diastolic pressure
What does ejection fraction (EF) measure?
Blood pressure
Heart rate variability
Percentage of EDV pumped out
Volume of blood remaining in the ventricle
What is cardiac reserve?
Amount of blood in reserve
Difference between resting and maximum CO
The heart's ability to withstand stress
The efficiency of the heart's electrical system
What is pulse pressure?
Average blood pressure
Difference between systolic and diastolic pressure
Pressure in the arteries during diastole
Force exerted by blood on arterial walls
What is the pathway of blood flow through the right side of the heart?
Aorta → Body → Vena cava → Right atrium
Pulmonary veins → Left atrium → Right ventricle → Pulmonary arteries
Vena cava → Right atrium → Tricuspid valve → Right ventricle → Pulmonary valve → Pulmonary arteries → Lungs
Lungs → Pulmonary veins → Left atrium → Mitral valve → Left ventricle
Which blood vessels carry oxygenated blood from the lungs to the heart?
Vena cava
Pulmonary arteries
Aorta
Pulmonary veins
Which characteristic is NOT a feature of cardiac muscle?
Striated
Involuntary
Voluntary
Intercalated discs
What is the function of intercalated discs in cardiac muscle?
Separate muscle fibers
Ensure electrical signal transmission and coordinated contraction
Store calcium ions
Produce ATP
What prevents tetany (sustained contraction) in cardiac muscle?
Rapid depolarization
Slow repolarization
Long refractory period
Short action potential duration
What does the P wave represent on an EKG?
Ventricular depolarization
Atrial depolarization
Ventricular repolarization
Atrial repolarization
Which EKG component reflects ventricular depolarization?
P wave
T wave
QRS complex
ST segment
What does the T wave on an EKG indicate?
Atrial depolarization
Ventricular repolarization
Ventricular depolarization
Atrial repolarization
Where are baroreceptors located?
Brain stem
Carotid sinuses, Aortic arch
Heart chambers
Blood vessels
What is the function of baroreceptors?
Detect changes in blood oxygen levels
Monitor blood pressure and adjust cardiac output
Regulate heart rate
Control blood vessel dilation
How does an increase in vessel radius affect blood flow?
Increases flow
Decreases flow
Has no effect
Causes turbulence
How does high blood viscosity impact blood flow?
Increases flow
Decreases flow
Has no effect
Improves oxygen delivery
What is the force that pushes fluid out of capillaries?
Hydrostatic pressure
Colloid osmotic pressure
Blood pressure
Osmotic pressure
What force pulls fluid into the capillaries?
Hydrostatic pressure
Colloid osmotic (oncotic) pressure
Blood pressure
Interstitial pressure
What is the primary function of the hepatic portal vein?
Deliver oxygenated blood to the liver
Carry blood from the liver to the heart
Filter blood
Transport nutrient-rich blood from digestive organs to the liver
Which of the following is NOT a branch of the aortic arch?
Brachiocephalic Artery
Left Common Carotid Artery
Right Common Carotid Artery
Left Subclavian Artery
What happens if the SA Node fails?
The heart stops beating.
The AV Node takes over, resulting in a slower heart rate.
The Purkinje fibers initiate the heartbeat.
The Bundle of His becomes the primary pacemaker.
What is the role of the Purkinje fibers in the heart's conduction system?
Delay the electrical signal.
Generate the initial electrical impulse.
Ensure coordinated ventricular contraction.
Transmit the signal from the atria to the ventricles.
Which heart valve is also known as the bicuspid valve?
Tricuspid valve
Pulmonary valve
Aortic valve
Mitral valve
What is the outermost layer of the heart wall called?
Myocardium
Endocardium
Epicardium
Pericardium
What is the term for the volume of blood ejected from the ventricle with each heartbeat?
Cardiac output
Stroke volume
End-diastolic volume
End-systolic volume
What is the correct order of the electrical events in the heart as seen on an EKG?
QRS complex, T wave, P wave
T wave, P wave, QRS complex
QRS complex, P wave, T wave
P wave, QRS complex, T wave
What is the main function of the baroreceptor reflex?
Control blood oxygen levels.
Regulate blood pressure.
Adjust heart rate based on body temperature.
Monitor blood glucose levels.
What factor has the most significant impact on blood flow resistance within a blood vessel?
Blood viscosity
Vessel length
Vessel radius
Blood pressure
What is the process of fluid movement out of capillaries into the interstitial space called?
Reabsorption
Diffusion
Filtration
Osmosis
Where does the hepatic portal vein receive blood from?
Heart
Lungs
Kidneys
Digestive organs
What is the role of the brachiocephalic artery?
Supplies blood to the left arm.
Supplies blood to the right arm and head.
Carries blood to the lungs.
Transports blood back to the heart.
Which of the following events marks the beginning of ventricular systole?
Closure of the AV valves
Opening of the semilunar valves
Atrial contraction
Isovolumetric contraction
What is the function of the chordae tendineae in the heart?
Contract the ventricles.
Open the semilunar valves.
Anchor the AV valve cusps to the papillary muscles.
Regulate the heart rate.
What happens to the pressure in the ventricles during isovolumetric contraction?
Decreases rapidly
Remains constant
Increases rapidly
Fluctuates irregularly
What causes the dicrotic notch in the aortic pressure curve?
Atrial contraction
Closure of the AV valves
Closure of the aortic valve
Opening of the pulmonary valve
What is the Frank-Starling law of the heart?
The strength of ventricular contraction is inversely proportional to the end-diastolic volume.
The strength of ventricular contraction is proportional to the end-diastolic volume.
The heart rate is determined by the autonomic nervous system.
The stroke volume is constant regardless of the preload.
What is the effect of sympathetic nervous system stimulation on the heart?
a) Decreases heart rate and contractility.
b) Increases heart rate and contractility.
c) Constricts blood vessels.
d) Reduces blood pressure.
