Chapter 20 - The Cardiovascular System: The Heart

Which wave in an electrocardiogram represents repolarization of the ventricles? R wave S wave P wave T wave Q wave

T Wave

Hypertension a. increases aortic pressure. b. decreases aortic pressure. c. decreases ventricular pressure. d. none of these

a. increases aortic pressure

The membrane that surrounds and protects the heart is called the a. pericardium. b. myocardium. c. pleura. d. mediastinum. e. endocardium.

a. pericardium

Which network of specialized cardiac muscle fibers provide a path for each cycle of cardiac excitation to progress through the heart? a. Systemic circuit b. Cardiac conduction system c. Pulmonary circuit d. Intercalated discs e. Cardiovascular center

b. Cardiac conduction system

In comparison to skeletal muscle fibers, the contractile fibers of the heart are depolarized for _____ period of time. a. the same b. a longer c. a shorter

b. a longer

Which of the following type of muscle contains the largest number of mitochondria per cell? a) Smooth muscle b) Skeletal muscle c) Cardiac muscle d) All the muscle types contain approximately the same number. e) Mitochondria are not found in muscle cells.

c) Cardiac Muscle

Which of the following would lead to a decreased heart rate? a) Increased norepinephrine release b) Increased thyroid hormone release c) Increased potassium levels in plasma d) Increased calcium levels in plasma e) Increased sympathetic stimulation

c) Increased potassium levels in plasma

Which valve below prevents blood from flowing back into the right ventricle? a) Tricuspid valve b) Bicuspid valve c) Pulmonary semilunar valve d) Aortic semilunar valve e) Mitral valve

c) Pulmonary semilunar valve

The P-wave in an electrocardiogram occurs during a. ventricular depolarization. b. ventricular repolarization. c. atrial depolarization. d. artial repolarization.

c. atrial depolarization.

When comparing cardiac muscle tissue to skeletal muscle tissue, which statement is true? a. both cardiac and skeletal muscle fibers are voluntary b. skeletal muscle fibers are connected by intercalated discs c. both types of fibers are striated d. skeletal muscle fibers are shorter e. there are more mitochondria in skeletal muscle fibers

c. both types of fibers are striated

Which of these periods represents greatest cardiac output? A. atrial diastole B. ventricular diastole C. atrial systole D. ventricular systole

(D) ventricular systole

This vessel distributes oxygenated blood to the myocardium. A. Coronary artery B. Coronary vein C. Right ventricle D. Left auricle E. Myocardial vein

(A) Coronary artery

This is the layer that protects the heart. A. Epicardium B. Pericardium C. Myocardial tissue D. Mediastinum E. Endocardium

(A) Epicardium

As each ventricle contracts where does blood move? A. Into an artery B. Into the apex C. Into a vein D. Through an atrioventricular valve E. Through the apex

(A) Into an artery

What type of tissue comprise the superficial fibrous pericardium? A. Dense regular connective tissue B. Dense irregular connective tissue C. Areolar connective tissue D. Hyaline cartilage E. Cardiac muscle tissue

(B) Dense irregular connective tissue

These extend into the auricle. A. Pectinate muscles B. Interatrial septum C. Coronary sulcus D. Ventricle E. Chordae tendinae

(C) Coronary sulcus

Cardiac muscle fibers electrically connect to neighboring fibers by A. Desmosomes B. Intermediate discs C. Gap junctions D. Contractile fibers E. Chordae tendinae

(C) Gap junctions

Which of the below reduces heart rate. A. Increased Norepinephrine hormone B. Increased Thyroid hormone C. Increased potassium levels D. Increased calcium levels E. Increased sympathetic stimulation

(C) Increased potassium levels

This part of the brain regulates heart rate. A. Cardiac accelerator nerves B. Chemoreceptors C. Medulla oblongata D. Vagus nerve E. Proprioceptors

(C) Medulla oblongata

Which of the below valves prevents blood from flowing back from the lungs? A. Tricuspid valve B. Bicuspid valve C. Pulmonary valve D. Aortic valve E. Pulmonary vein

(C) Pulmonary valve

From the left ventricle, where does blood pass? A. Right atrium B. Right ventricle C. Bicuspid valve D. Aortic semilunar valve E. Pulmonary trunk

(D) Aortic semilunar valve

This is the mass of tissue from the sternum to the vertebral column between the lungs. A. Epicardium B. Parietal layer C. Pericardial tissue D. Mediastinum E. Fibrous cardium

(D) Mediastinum

This electrical event triggers contraction of the atria. A. R wave B. T wave C. S wave D. P wave E. Q wave

(D) P wave

The second heart sound represents which of the below events? A. Valvular stenosis B. Semilunar valves opening C. Atrioventricular valves closing D. Semilunar valves closing E. Atrioventricular valves opening

(D) Semilunar valves closing

This part of the heart can initiate a contraction and can set a constant heart rate of about 100 beats per minute. A. Cardiac accelerator nerves B. Chemoreceptors C. Cardiovascular center D. Sinoatrial node E. Proprioceptors

(D) Sinoatrial node

As each atrium contracts where does blood move? A. Into an auricle B. Into an artery C. Into a vein D. Through an atrioventricular valve E. Through a semilunar valve

(D) Through an atrioventricular valve

This marks the boundary between the ventricles. A. Coronary sulcus B. Anterior interventricular sulcus C. Posterior interventricular sulcus D. Coronary sulcus and posterior interventricular sulcus E. Anterior and posterior interventricular sulcus

(E) Anterior and posterior interventricular sulcus

The intercalated discs seen in cardiac myocytes 1. have desmosomes which help to hold the muscle fibers together. 2. have gap junctions which allow action potentials to conduct from one muscle fiber to the next. 3. are the result of actin/myosin overlap. 1 only 2 only 3 only 1 and 2 are correct. 1, 2 and 3 are correct.

1 and 2 are correct

What is the function of foramen ovale during fetal life? A.Allowing blood to flow directly from the right atrium into the left atrium. B.Allowing blood to flow directly from the right ventricle into the left ventricle. C.Serves as a valve in the vena cava to regulate venous blood flow. D.Prevents back flow of blood from aorta into the left ventricle. E.Prevents back flow of blood from pulmonary trunk into the right ventricle.

A. Allowing blood to flow directly from the right atrium into the left atrium.

What type of tissue comprises the valves of the heart? A.Dense connective tissue B.Areolar connective tissue C.Hyaline cartilage D.Cardiac muscle tissue E.Adipose tissue

A. Dense connective tissue

This layer of the heart wall consists of mesothelium and connective tissue. A.Epicardium B.Myocardium C.Endocardium D.Fibrous pericardium E.None of the answer selections are correct

A. Epicardium

These muscular ridges are found on the anterior wall of the right atrium and extend into the auricles. A.Pectinate muscles B.Trabeculae carneae C.Coronary sulci D.Papillary muscles E.Chordae tendinae

A. Pectinate muscles

Contraction of the ventricles of the heart leads to blood moving directly A.into arteries. B.into capillaries. C.into veins. D.through an atrioventricular valve. E.through the apex.

A. into arteries.

Heart murmurs are often heard in individuals with abnormalities in the ______ of the heart. A.valves B.myocardium C.SA node D.AV node E.endocardium

A. valves

Does blood ever flow backwards in the heart?

As the atria contracts a small amount of blood flows backwards into the vena cava or the pulmonary veins.

Which of the following statements is NOT correct? A) The walls of the ventricles are thicker because the ventricles pump blood under higher pressure over greater distances. B) The walls of the atria are thicker because the atria receive blood under pressure. C) The wall of the right ventricle is thinner than that of the left ventricle because the right side of the heart pumps blood a shorter distance at lower pressure. D) Although the right side of the heart has a smaller workload, the right and left ventricle simultaneously eject the same amount of blood. E) All of the above are correct.

B) The walls of the atria are thicker because the atria receive blood under pressure.

In comparison to a sedentary individual, a well-trained athlete will usually have all the following characteristics EXCEPT A.a higher cardiac reserve. B.a higher resting cardiac output. C.a higher stroke volume. D.hypertrophy of the heart. E.resting bradycardia.

B. a higher resting cardiac output.

The apex of the heart is normally pointed A.at the midline. B.to the left of the midline. C.to the right of the midline. D.is different for males and females E.posteriorly.

B. to the left of the midline.

The anatomical region found between the lungs that extends from the sternum to the vertebral column and from the first rib to the diaphragm. A.Epicardium B.Abdominal cavity C.Pericardium D.Mediastinum E.Thoracic cavity

D.Mediastinum

Through which structure does blood pass from the right atrium to the right ventricle? A.Bicuspid valve B.Interventricular septum C.Tricuspid valve D.Mitral valve E.Ascending aorta

C. Tricuspid valve

The process of listening to heart sounds using a stethoscope is referred to as A.palpitation. B.palpation. C.auscultation. D.fibrillation. E.echocardiography.

C. auscultation.

Cardiac output is the volume of blood ejected from the ______ ventricle into the _____ each minute. A.left, aorta B.right, aorta C.left or right, aorta or pulmonary trunk D.right, pulmonary trunk E.both left and right aorta are correct

C. left or right, aorta or pulmonary trunk

Stimulation of this nerve reduces heart rate. A. Cardiac accelerator nerve B. Hypoglossal nerve C. Medulla oblongata nerve D. Vagus nerve E. Phrenic nerve

D) Vagus nerve

Which of the following is a disorder in which the aortic semilunar valve is narrowed? A.Aortic insufficiency B.Rheumatic fever C.Mitral valve prolapse D.Aortic stenosis E.Mitral insufficiency

D. Aortic stenosis

The difference between a person's maximum cardiac output and resting cardiac output is called the A.stroke volume. B.peripheral resistance. C.afterload. D.cardiac reserve. E.venous return.

D. cardiac reserve.

In a fetus, this structure allows blood to flow directly from the pulmonary trunk into the aorta. A.Fossa ovalis B.Foramen ovale C.Trabeculae carneae D.Descending aorta E.Ductus arteriosus

E. Ductus arteriosus

A corrective cardiac procedure in which a large piece of a patient's own latissimus dorsi muscle is wrapped around the heart and stimulated by an implanted pacemaker to assist the pumping action of a damaged heart. A.myocardial infarction B.tetrology of Fallot C.cardiomyopathy D.cardiomegaly E.cardiomyoplasty

E. cardiomyoplasty

Cardiac output can be determined by multiplying the heart rate by the stroke volume. True False

True

Contraction of the cardiac muscle sarcomeres during ventricular systole provides the force needed to eject blood from the heart. True False

True

Parasympathetic nervous system stimulation of the heart has little effect on force of contraction because the vagus nerve does not supply most of the ventricular myocytes. True False

True

Semilunar valves close during ventricular diastole to prevent blood from flowing from the aortas into the ventricles. True False

True

The semilunar valves open when pressure in the right and left ventricles exceeds that in the pulmonary trunk and aorta, respectively. True False

True

When all heart valves are closed during isovolumetric ventricular contraction, the amount of blood (volume) is constant but blood pressure increases. True False

True

A skeletal muscle may undergo tetanus but cardiac muscle cannot. a) True b) False

a) True

The volume of blood ejected from the left ventricle into the aorta each minute is called the a) cardiac output. b) cardiac input. c) stroke volume. d) heart rate. e) pulse pressure.

a) cardiac output

Which represents the correct flow of excitation through the cardiac conduction system? a. SA node, AV node, bundle of His, right and left bundle branches, Purkinje fibers b. right and left bundle branches, bundle of His, SA node, AV node, Purkinje fibers c. Purkinje fibers, right and left bundle branches, bundle of His, AV node, SA node d. AV node, SA node, bundle of His, right and left bundle branches, Purkinje fibers e. AV node, SA node, bundle of His, Purkinje fibers, right and left bundle branches

a. SA node, AV node, bundle of His, right and left bundle branches, Purkinje fibers

Which of the following places the phases of the cardiac cycle in correct order? a. isovolumetric contraction, atrial contraction, ventricular filling, ventricular ejection, isovolumetric relaxation, atrial contraction b. atrial contraction, isovolumetric contraction, ventricular ejection, isovolumetric relaxation, ventricular filling, atrial contraction c. atrial contraction, isovolumetric contraction, ventricular filling, isovolumetric relaxation, ventricular ejection, atrial contraction d. atrial contraction, isovolumetric relaxation, ventricular ejection, isovolumetric contraction, ventricular filling, atrial contraction e. atrial contraction, isovolumetric relaxation, ventricular filling, isovolumetric contraction, ventricular ejection, atrial contraction

b. atrial contraction, isovolumetric contraction, ventricular ejection, isovolumetric relaxation, ventricular filling, atrial contracti

Blood leaves the heart during a. ventricular relaxation b. ventricular ejection (contraction) c. isovolumetric ventricular relaxation d. passive ventricular filling

b. ventricular ejection

During which of following periods does the largest volume of blood enter the arteries? a. atrial diastole b. ventricular systole c. ventricular diastole d. atrial systole

b. ventricular systole

The first sound heard in a stethoscope during the cardiac cycle is the a. contraction of the atria b. contraction of the ventricles c. closing of the AV valves d. closing of the semilunar valves

c. closing of the AV valves

The visceral layer of the serous pericardium: a. is fused to the fibrous pericardium b. is the fluid that offers protection to the heart c. is the outer layer of the heart d. is a tough, inelastic layer that anchors the heart in the mediastinum e. is also called the pericardial cavity

c. is the outer layer of the heart

Which of the following is the correct pathway of blood starting at the right atrium? a. right atrium, left atrium, left ventricle, right ventricle, pulmonary trunk, pulmonary veins, aorta b. right atrium, aorta, left ventricle, left atrium, pulmonary trunk, right ventricle, pulmonary veins c. right atrium, right ventricle, pulmonary trunk, pulmonary veins, left atrium, left ventricle, aorta d. right atrium, pulmonary trunk, left atrium, left ventricle, pulmonary veins, aorta, right ventricle

c. right atrium, right ventricle, pulmonary trunk, pulmonary veins, left atrium, left ventricle, aorta

Atrial repolarization occurs during ventricular depolarization and, consequently, would be viewed on an electrocardiogram (if it was visible) during a. both the P-wave and the T-wave. b. the P-wave. c. the QRS complex. d. the T-wave.

c. the QRS complex.

what occurs after the QRS phase of the ECG? a. the atria contract. b. the atria relax. c. the ventricles contract. d. the ventricles relax. e. diastole occurs.

c. the ventricles contract.

Which of the following electrocardiogram (EKG) waves represents atrial depolarization? a) R wave b) T wave c) S wave d) P wave e) Q wave

d) P wave

Which structure in the heart initiates action potentials that stimulate contraction of the heart at constant rate of about 100 beats per minute? a) Cardiac accelerator nerves b) Atrioventricular node c) Cardiovascular center d) Sinoatrial node e) Bundle of His

d) Sinoatrial node

Contraction of the atria of the heart leads to blood moving directly a) into auricles. b) into arteries. c) into veins d) through atrioventricular valves e) through semilunar valves.

d) through atrioventricular valves

Which layer of the heart wall consists of cardiac muscle tissue? a. Hypocardium b. Pericardium c. Epicardium d. Myocardium e. Endocardium

d. Myocardium

Which of the following correctly lists the sequence of structures that a cardiac action potential follows in order to excite normal contraction of the heart? a. Bundle of His, Purkinje fibers, Atrioventricular (AV) node b. Purkinje fibers, AV node, SA node, Bundle of His c. Bundle of His, SA node, AV node, Purkinje fibers d. SA node, AV node, Bundle of His, Purkinje fibers e. Sinoatrial (SA) node, Purkinje fibers, AV node, Bundle of His

d. SA node, AV node, Bundle of His, Purkinje fibers

What is occurring during isovolumetric contraction? a. the amount of blood in each atria is the same b. the semilunar valves are open and the AV valves are closed c. the point at which all blood has been ejected from the ventricles d. all four valves are closed e. both atria are ejecting blood at the same time

d. all four valves are closed

Ventricular muscle is relaxed a. during ventricular diastole b. approximately half of the cardiac cycle c. during atrial systole d. all of the above

d. all of the above

The amount of blood ejected from either ventricle every minute is called: a. stroke volume b. end-diastolic volume c. afterload d. cardiac output e. heart rate

d. cardiac output

Prolapse of the atrioventricular valves is prevented by a. the fibrous skeleton of the heart. b. increasing blood pressure in the ventricles. c. contraction of the pectinate muscles. d. contraction of the papillary muscles. e. contraction of the chordae tendineae.

d. contraction of the papillary muscles.

Atrial systole is necessary to a. close the AV valves b. allow blood to passively fill the chambers c. fill the aortas with blood d. fill the ventricles with blood

d. fill the ventricles with blood

Which of the following selections lists conditions that would lead to increased stroke volume? a. decreased preload, decreased afterload, decreased contractility b. increased preload, increased afterload, decreased contractility c. increased preload, increased afterload, increased contractility d. increased preload, decreased afterload, increased contractility e. decreased preload, increased afterload, increased contractility

d. increased preload, decreased afterload, increased contractility

The right side of the heart is concerned with a. two of the choices are correct b. pumping oxygenated blood c. systemic circulation d. pulmonary circulation

d. pulmonary circulation

Towards the end of ventricular systole when ventricular blood pressure exceeds aortic blood pressure a. semilunar valves close b. AV valves open c. AV valves close d. semilunar valves open

d. semilunar valves open

Which term refers to the period of time during a cardiac cycle when contraction of a chamber occurs and pressure within the chamber rises? a. diastole b. fibrillation c. filling d. systole e. repolarization

d. systole

Semilunar valves function to prevent blood from flowing back into the a. atria during atrial diastole b. ventricles during ventricular systole c. atria during atrial systole d. ventricles during ventricular diastole

d. ventricles during ventricular diastole

Isovolumetric contraction is the phase of the cardiac cardiac cycle in which a. atrial depolarization occurs. b. the semilunar valves are open. c. ventricular repolarization occurs. d. ventricular pressure increases and ventricular volume remains the same. e. oxygenated blood leaves the heart into the systemic circulation.

d. ventricular pressure increases and ventricular volume remains the same.

dentify the pouch-like structure that increases the total filling capacity of the atrium. a. Ventricle b. Coronary sulcus c. Fossa ovalis d. Interatrial septum e. Auricle.

e. Auricle.

Which of the following is used to reduce friction between the layers of membranes surrounding the heart? a. Capillary endothelium b. Endocardium c. Pleural fluid d. Synovial fluid e. Pericardial fluid

e. Pericardial fluid

What of the following chambers of the heart contain deoxygenated blood? a. Right ventricle only b. Left atrium and right ventricle c. Left atrium and left ventricle d. Left atrium only e. Right atrium and right ventricle

e. Right atrium and right ventricle

Stimulation of which nerve reduces heart rate? a. Hypoglossal nerve b. Spinal accessory c. Phrenic nerve d. Cardiac accelerator nerve e. Vagus nerve

e. Vagus nerve

The atria receive blood from all of the following except: a. pulmonary veins b. superior vena cava c. coronary sinus d. inferior vena cava e. all of these choices supply blood to the atria

e. all of these choices supply blood to the atria

The outermost layer of the pericardium, which consists of inelastic dense irregular connective tissue, is called the a. endocardium. b. epicardium. c. parietal layer of pericardium. d. serous pericardium. e. fibrous pericardium.

e. fibrous pericardium.