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

Question 1

The _____ period follows depolarization of the myocardium and represents a period during which no new cardiac potential can be propagated.

A) absolute refractory
B) hyperpolarization
C) resting
D) threshold

Answer 1

absolute refractory

Question 2

A 52-year-old female is admitted to the cardiac unit with a diagnosis of pericarditis. She asks the nurse to explain where the infection is. In providing an accurate description, the nurse states that the pericardium is:

A) the outer muscular layer of the heart.
B) the innermost lining of the heart chambers.
C) a membranous sac that encloses the heart.
D) the heart's fibrous skeleton.

Answer 2

a membranous sac that encloses the heart.

Question 3

Depolarization of a cardiac muscle cell occurs as the result of:

A) a decrease in the permeability of the cell membrane to ions.
B) the rapid movement of ions across the cell membrane.
C) a blockade by calcium ions.
D) stimuli instigated during the refractory period.

Answer 3

the rapid movement of ions across the cell membrane.

Question 4

Oxygenated blood flows through the:

A) superior vena cava.
B) pulmonary veins.
C) pulmonary artery.
D) cardiac veins.

Question 5

The chamber that receives blood from the systemic circulation is the:

A) right atrium.
B) right ventricle.
C) left atrium.
D) left ventricle.

Question 6

In a normal electrocardiogram, the P-R interval represents:

A) atrial depolarization.
B) ventricular depolarization.
C) onset of atrial activation to onset of ventricular activity.
D) "electrical systole" of the ventricles.

Question 7

The _____ represents the sum of all ventricular muscle cell depolarization.

A) PR interval
B) QRS complex
C) QT interval
D) P wave

Question 8

A 65-year-old male develops blockage in the pulmonary artery. As a result, blood would first back up into the:

A) aorta.
B) left ventricle.
C) pulmonary veins.
D) right ventricle.

Question 9

A 50-year-old female received trauma to the chest that caused severe impairment of the primary pacemaker cells of the heart. Which of the following areas received the greatest damage?

A) AV node
B) SA node
C) Bundle of His
D) Ventricles

Question 10

The _____ artery travels down the interventricular septum and delivers blood to portions of the left and right ventricle.

A) right coronary
B) circumflex
C) left anterior descending
D) cardiac

Question 11

A function of the pericardium is to:

A) provide a barrier against extracardial infections.
B) improve blood flow through the heart.
C) play a role in cardiac conduction.
D) assist in cardiac contraction.

Question 12

A 54-year-old male is diagnosed with left bundle branch block. Which of the following structures would not receive an electrical impulse?

A) AV node
B) SA node
C) Bundle of His
D) The left ventricles

Question 13

A 20-year-old male underwent an echocardiogram to assess chest pain. Results revealed a congenital defect in papillary muscles. Which of the following would occur?

A) Semilunar valve closure
B) Backward expulsion of the atrioventricular valves
C) Atrioventricular valve closure
D) Backward expulsion of the semilunar valves

Question 14

A 13-year-old female took a weight loss drug that activated the sympathetic nervous system. Which of the following would be expected?

A) Decreased myocardial contraction
B) Decreased heart rate
C) Increased cardiac cycle speed
D) Increased intranodal conduction time

Question 15

Venous blood from the coronary circulation drains into the:

A) superior vena cava.
B) inferior vena cava.
C) right atrium.
D) left atrium.

Question 16

The coronary ostia (the openings to the coronary arteries) are found in the:

A) left ventricle.
B) inferior vena cava.
C) coronary sinus.
D) aorta.

Question 17

A 65-year-old male is transported to the ER for chest pain. An electrocardiogram reveals a prolonged QRS interval. This result indicates:

A) increased ejection time.
B) increased isovolumetric contraction time.
C) mitral valve opening.
D) aortic valve closing.

Question 18

_____ are the anchors of the atrioventricular valves.

A) Chordae tendineae cordis
B) Great vessels
C) Coronary ostia
D) Trabeculae carneae

Question 19

The chamber of the heart that generates the highest pressure is the:

A) right atrium.
B) left atrium.
C) left ventricle.
D) right ventricle.

Question 20

The _____ conducts action potentials down the atrioventricular septum.

A) Bachmann bundle
B) bundle of His
C) sinoatrial node
D) atrioventricular node

Question 21

Pressure in the left ventricle must exceed pressure in the _____ before the left ventricle can eject blood.

A) coronary arteries
B) aorta
C) inferior vena cava
D) pulmonary veins

Question 22

_____ are thickened areas of the sarcolemma of myocardial cells that enable electrical impulses to travel in a continuous cell-to-cell fashion.

A) Sclerotic plaques
B) Intercalated disks
C) Crossbridges
D) A-bands

Question 23

The internal lining of the cardiovascular system is formed by what tissue?

A) Columnar epithelium
B) Connective
C) Mesothelium
D) Endothelium

Question 24

Multiplying heart rate by stroke volume determines:

A) vascular resistance.
B) preload.
C) cardiac output.
D) ejection fraction.

Question 25

_____ is the pressure generated at the end of diastole.

A) Preload
B) Afterload
C) Systemic vascular resistance
D) Total peripheral resistance

Question 26

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.

A) pressure, duration
B) volume, force
C) viscosity, force
D) viscosity, duration

Question 27

One difference between cardiac muscle and skeletal muscle is that:

A) cardiac muscle cells are arranged in branching networks.
B) skeletal muscle cells have only one nucleus.
C) cardiac muscle cells appear striped.
D) skeletal muscle cells contain sarcomeres.

Question 28

Within a normal physiologic range, an increase in left ventricular end-diastolic volume leads to:

A) an increased force of contraction.
B) a decrease in cardiac output.
C) an increase in heart rate.
D) heart failure.

Question 29

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

A) troponin C.
B) troponin I.
C) troponin T.
D) myosin.

Question 30

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

A) renal retention of fluids.
B) depressed myocardial contractility.
C) release of acetylcholine.
D) increased heart rate.

Question 31

A new drug is released to aid in weight loss. It stimulates the sympathetic system to increase heart rate by:

A) inhibiting the release of catecholamines.
B) altering the threshold potential.
C) decreasing the conduction time through the AV node.
D) increasing the influx of calcium.

Question 32

The Bainbridge reflex:

A) increases the heart rate after intravenous infusions.
B) decreases blood pressure in response to baroreceptors.
C) increases the rate and depth of respiration.
D) decreases myocardial contractility.

Question 33

The effect of acetylcholine on the heart is to:

A) decrease the refractory period.
B) increase calcium influx.
C) increase the strength of myocardial contraction.
D) decrease the heart rate.

Question 34

The primary cardiovascular control center is located in the:

A) cerebral cortex.
B) midbrain.
C) medulla.
D) cervical spinal cord.

Question 35

Right ventricular afterload is determine by:

A) vascular resistance in the systemic vessels.
B) right end-diastolic pressure.
C) pressures in the vena cavae.
D) pulmonary vascular resistance.

Question 36

The cardiac electrical impulse normally begins spontaneously in the SA node because:

A) of its superior location in the right atrium.
B) it is the only area of the heart capable of spontaneous depolarization.
C) it has rich sympathetic innervation via the vagus nerve.
D) it depolarizes more rapidly than other automatic cells of the heart.

Question 37

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

A) Increased speed of cardiac cycle
B) Increased cardiac contractility
C) Decreased vasodilation
D) Decreased cardiac conduction

Question 38

Which of the following occurs during muscle contraction?

A) Decreased distance between Z lines
B) Decreased A band length
C) Decreased Z line length
D) Increased H zone distance

Question 39

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?

A) Acetylcholine
B) Dopamine
C) Epinephrine
D) Thyroid hormone

Question 40

_____ 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.

A) Electrocontraction
B) Intercalated communication
C) Excitation-contraction coupling
D) Myosin communication

Question 41

The thoracic lymphatic duct drains into the:

A) right subclavian artery.
B) right atrium.
C) right subclavian vein.
D) left subclavian vein.

Question 42

One of the most important mechanisms for maintaining venous return to the right atrium is:

A) cardiac output.
B) capillary hydrostatic pressure.
C) skeletal muscle contraction.
D) respiratory cycling.

Question 43

Baroreceptors are located in the:

A) renal artery.
B) superior vena cava.
C) carotid sinus.
D) circle of Willis.

Question 44

In the renin-angiotension-aldosterone system, conversion of angiotensin I to angiotensin II happens in the:

A) lungs.
B) liver.
C) kidneys.
D) heart.

Question 45

Local myogenic regulation of blood vessel diameter and thus blood flow through a vessel is an example of:

A) autonomic regulation.
B) somatic regulation.
C) autoregulation.
D) metabolic regulation.

Question 46

Poiseuille formula states that resistance to blood flow is inversely related to:

A) blood viscosity.
B) blood vessel diameter.
C) blood pressure.
D) blood vessel length.

Question 47

Which of the following statements correctly describes a direct end effect of the renin-angiotension-aldosterone system?

A) Angiotension II causes systemic vasoconstriction.
B) Renin promotes the excretion of sodium and water in the renal tubules.
C) Aldosterone increases renal retention of water only.
D) Angiotension I promotes sodium and water reabsorption by the kidneys.