Question 1

A cardiologist is teaching about myocardial cells.Which information should the cardiologist include? _____ are thickened areas of the sarcolemma of myocardial cells that enable electrical impulses to travel in a continuous cell-to-cell fashion.

Accepted Answer

Intercalated discs allow electrical impulses to be transmitted rapidly from cardiac fiber to cardiac fiber because the network of fibers is connected at these discs.
Myosins are filaments that are a part of cardiac tissue.They do not play a role in conduction.
Troponin Ts are involved in contraction,but are not part of the sarcolemma.
I bands are a part of the filaments bud,which do not conduct impulses in a cell-to-cell fashion.

Question 2

A patient has searched on the internet for muscle contractions.Which information indicates a good understanding? Muscle contractions occur when there is a decreased:

Accepted Answer

Anatomically,contraction occurs when the sarcomere shortens,so adjacent Z lines move closer together.
Anatomically,contraction occurs when the sarcomere shortens,so adjacent Z lines move closer together,not a decrease in A band length.
Anatomically,contraction occurs when the sarcomere shortens,so adjacent Z lines move closer together,not a decrease in Z line length.
Anatomically,contraction occurs when the sarcomere shortens,so adjacent Z lines move closer together,not a decrease in H zone distance.

Question 3

Which principle should the nurse remember when planning nursing care for a patient with heart problems? As stated by the Frank-Starling law,there is a direct relationship between the _____ of the blood in the heart at the end of diastole and the _____ of contraction during the next systole.

Accepted Answer

The Frank-Starling law of the heart describes the length-tension relationship of ventricular end-diastolic volume (VEDV)(preload)to myocardial contractility (as measured by stroke volume).
The Frank-Starling law of the heart describes the length-tension relationship of VEDV (preload)to myocardial contractility (as measured by stroke volume).It does not refer to duration.
The Frank-Starling law of the heart describes the length-tension relationship of VEDV (preload)to myocardial contractility (as measured by stroke volume).It does not refer to viscosity.
The Frank-Starling law of the heart describes the length-tension relationship of VEDV (preload)to myocardial contractility (as measured by stroke volume).It does not refer to duration.

Question 4

A 50-year-old female was prescribed a drug that acts as a negative inotrope.Which of the following endogenous substances would be most similar?

Accepted Answer

The most important negative inotropic agent is acetylcholine.
The most important negative inotropic agent is acetylcholine,not dopamine,which is a positive inotrope.
The most important negative inotropic agent is acetylcholine,not epinephrine,which is a positive inotrope.
The most important negative inotropic agent is acetylcholine,not thyroid hormone,which is a positive inotrope.

Question 5

A new drug is released to aid in weight loss.It stimulates the sympathetic system.The nurse monitors for an increased heart rate.The sympathetic system causes this by:

Accepted Answer

The sympathetic system increases heart rate by altering the threshold potential.
The sympathetic system increases heart rate by altering the threshold potential.It does not inhibit the release of catecholamines.
The sympathetic system increases heart rate by altering the threshold potential.It does not decrease conduction through the AV node.
The sympathetic system increases heart rate by altering the threshold potential.It does not increase the influx of calcium.

Question 6

When a student nurse asks the nurse how the cardiac electrical impulse normally begins,what is the most correct response? The cardiac electrical impulse normally begins spontaneously in the sinoatrial (SA)node because it:

Accepted Answer

The electrical impulse normally begins in the SA node because its cells depolarize more rapidly than other automatic cells.
Cardiac impulses occur in the SA node because its cells depolarize more rapidly than other automatic cells,not because of its superior location.
Cardiac impulses occur in the SA node because its cells depolarize more rapidly than other automatic cells.The SA node is not the only area of the heart capable of spontaneous depolarization.
Cardiac impulses occur in the SA node because its cells depolarize more rapidly than other automatic cells.It does have rich innervations,but by parasympathetic innervation from the vagus nerve.

Question 7

The molecule that aids in bonding of the troponin complex to actin and tropomyosin is troponin:

Accepted Answer

Troponin T aids in the binding of the troponin complex to actin and tropomyosin.
Troponin C contains binding sites for the calcium ions involved in contraction.
Troponin I inhibits the ATPase of actomyosin.
Troponin M is not a substance.

Question 8

A nurse assesses the heart after acetylcholine because the effect of acetylcholine on the heart is to:

Accepted Answer

Acetylcholine causes decreased heart rate and slows conduction through the atrioventricular (AV)node.
Acetylcholine causes decreased heart rate and slows conduction through the AV node; it does not decrease the refractory period.
It decreases calcium influx.
Acetylcholine causes decreased heart rate and slows conduction through the AV node; it does not increase the strength of myocardial contraction.

Question 9

A nurse recalls the internal lining of the cardiovascular system is formed by what tissue?

Accepted Answer

The endothelium is the lining of blood vessels.
The endothelium,not the tunica adventitia,is the lining of blood vessels.
Connective tissues help make up arterial walls but are not the lining of blood vessels.
The mesothelium is a part of the pericardial cavity.

Question 10

_____ is the process by which an action potential in the plasma membrane of a myocardial cell triggers the events that directly cause contraction of the myocardial cells.

Accepted Answer

Excitation-contraction coupling is the process by which an action potential in the plasma membrane of the muscle fiber triggers the cycle,leading to cross-bridge activity and contraction.
Excitation-contraction coupling,not electrocontraction,is the process by which an action potential in the plasma membrane of the muscle fiber triggers the cycle,leading to cross-bridge activity and contraction.
Excitation-contraction coupling,not intercalated communication,is the process by which an action potential in the plasma membrane of the muscle fiber triggers the cycle,leading to cross-bridge activity and contraction.
Excitation-contraction coupling,not myosin communication,is the process by which an action potential in the plasma membrane of the muscle fiber triggers the cycle,leading to cross-bridge activity and contraction.

Question 11

Within a normal physiologic range,an increase in left ventricular end-diastolic volume would lead the nurse to monitor for:

Accepted Answer

An increase in end-diastolic volume leads to an increased force of contraction because fibers are stretched to handle increased volume.
Cardiac output would increase.
Although volume increases,heart rate does not respond accordingly.
An increase in end-diastolic volume would not lead to heart failure.Failure results in output decrease.

Question 12

Which principle should the nurse remember while planning care for a cardiac patient? Pressure in the left ventricle must exceed pressure in the _____ before the left ventricle can eject blood.

Accepted Answer

The pressure in the left ventricle must override that of the aorta before the ventricle can eject blood.
The pressure in the left ventricle must override that of the aorta,not the coronary arteries,before the ventricle can eject blood.
The pressure in the left ventricle must override that of the aorta,not the inferior vena cava,before the ventricle can eject blood.
The pressure in the left ventricle must override that of the aorta,not the pulmonary veins,before the ventricle can eject blood.

Question 13

A 50-year-old female presents with a low heart rate and low blood pressure.She is given an intravenous (IV)infusion of fluids.The increase in atrial distension results in:

Accepted Answer

IV fluids increase intravascular volume,distending the atria and increasing the heart rate.
IV fluids increase intravascular volume,distending the atria and increasing the heart rate; it does not result in renal retention of fluids.
IV fluids increase intravascular volume,distending the atria and increasing the heart rate; it does not depress myocardial contractility.
IV fluids increase intravascular volume,distending the atria and increasing the heart rate; it does not result in the release of acetylcholine.

Question 14

After activation of the Bainbridge reflex in a patient,the nurse assesses for:

Accepted Answer

Activation of the Bainbridge reflex increases heart rate.
Activation of the Bainbridge reflex increases heart rate; it does not decrease blood pressure.
Activation of the Bainbridge reflex increases heart rate; it does not increase rate and depth of respirations.
Activation of the Bainbridge reflex increases heart rate; it does not decrease myocardial contractility.

Question 15

While planning care for a heart patient,which principle should the nurse recall? Right ventricular afterload is affected by:

Accepted Answer

Right ventricular afterload is affected by pulmonary vascular resistance because this is the pressure the ventricle must pump against.
Systemic resistance affects left-sided afterload.
Right end-diastolic pressure is a measurement of the pressure at diastole,but does not determine afterload.
Pressures in the vena cava do not affect right ventricle afterload directly.

Question 16

A nurse observes a cardiologist multiplying the heart rate by stroke volume.What is the cardiologist measuring?

Accepted Answer

Cardiac output is found by multiplying the heart rate times stroke volume.
Vascular resistance is not a factor in the calculation of cardiac output; it does play a role in blood pressure.
Preload affects cardiac output but is not the result of heart rate times stroke volume.
Ejection fraction is the amount ejected per beat.

Question 17

A nurse is discussing the pressure generated at the end of diastole.Which term is the nurse describing?

Accepted Answer

Preload is the volume and associated pressure generated in the ventricle at the end of diastole.
B Preload,not afterload,is the volume and associated pressure generated in the ventricle at the end of diastole.Afterload is the resistance to ejection of blood from the left ventricle.
Systemic vascular resistance is related to afterload.
Total peripheral resistance increases afterload.

Question 18

To help a nursing student differentiate cardiac muscle from skeletal muscle,which characteristic should the nurse use? One difference between cardiac muscle and skeletal muscle is that:

Accepted Answer

Cardiac cells are arranged in branching networks throughout the myocardium,whereas skeletal muscle cells tend to be arranged in parallel units throughout the length of the muscle.
Cardiac muscle cells have only one nucleus,whereas skeletal muscle cells have many nuclei.
Both cardiac and muscle cells appear striped.
Both cardiac and muscle cells contain sarcomeres.

Question 19

When a nursing student wants to know where the primary cardiovascular control center is located,what is the nurse's best response? In the:

Accepted Answer

The cardiovascular control center is in the brainstem in the medulla.
The cardiovascular control center is in the brainstem in the medulla,not the cerebral cortex.The cardiovascular control center is in the brainstem in the medulla,not the midbrain.
The cardiovascular control center is in the brainstem in the medulla,not in the cervical spinal cord.

Question 20

A 28-year-old female with seizure disorder has a vagus nerve stimulator implanted to help control seizure activity.Which of the following would the nurse also expect to occur?

Accepted Answer

The vagus nerve releases acetylcholine.Acetylcholine causes decreased heart rate and slows conduction through the atrioventricular (AV)node.
The vagus nerve releases acetylcholine.Acetylcholine causes decreased heart rate and slows conduction through the AV node,thus decreasing speed of the cardiac cycle.
The vagus nerve releases acetylcholine.Acetylcholine causes decreased heart rate and slows conduction through the AV node,decreasing contractility.
The vagus nerve releases acetylcholine.Acetylcholine causes decreased heart rate and slows conduction through the AV node; it does not cause vasodilation.

Quiz 22: Structure and Function of the Cardiovascular and Lymphatic Systems