Chapter 20: The Cardiovascular System: The Heart a

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

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

Which wave in an electrocardiogram represents repolarization of the ventricles? A.R wave B.T wave C.S wave D.P wave E.Q wave

B. T wave

During heart transplants, the ________ nerves are severed resulting in a faster resting heart rate (approximately 100 beats per minute) after the transplant. A.glossopharyngeal B.cardiac accelerator C.vagus D.phrenic E.cervical spinal

C. vagus

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

D. Vagus nerve

This pouch-like structure increases the total filling capacity of the atrium. A.Ventricle B.Coronary sulcus C.Fossa ovalis D.Interatrial septum E.Auricle.

E. Auricle.

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

In comparison to skeletal muscle fibers, the contractile fibers of the heart are depolarized for ____ period of time. A.a shorter B.a longer C.the same

B. a longer

Which of the following conditions would lead to an increase in the afterload for the ventricles thus lowering stroke volume and cardiac output? A.hypotension B.hypertension C.increased venous return D.decreased venous return E.positive inotropic agents

B. hypertension

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.

Which of the following blood vessels is used to distribute oxygenated blood to the myocardium? A.Coronary artery B.Coronary vein C.Coronary sinus D.Vena cava E.Myocardial vein

A. Coronary artery

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

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

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.

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.

The membrane that surrounds and protects the heart is called the A.pericardium. B.pleura. C.myocardium. D.mediastinum. E.endocardium.

A. pericardium.

This groove found on the surface of the heart marks the boundary between the right and left ventricles. A.Coronary sulcus B.Anterior interventricular sulcus C.Posterior interventricular sulcus D.Coronary sinus E.Anterior intraventricular sulcus

B. Anterior interventricular sulcus

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.

This term refers to the period of time during a cardiac cycle when contraction of a chamber occurs and pressure within the chamber rises. A.filling B.systole C.repolarization D.diastole E.fibrillation

B. systole

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.

Which of the following types 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 of the following selections lists conditions that would lead to increased stroke volume? A.increased preload, increased afterload, increased contractility B.decreased preload, decreased afterload, decreased contractility C.increased preload, decreased afterload, increased contractility D.decreased preload, increased afterload, increased contractility E.increased preload, increased afterload, decreased contractility

C. Increased preload, decreased afterload, increased contractility

This part of the brain contains the cardiovascular center that regulates heart rate. A.Midbrain B.Cerebrum C.Medulla oblongata D.Cerebellum E.Thalamus

C. Medulla oblongata

Which layer of the heart wall consists of cardiac muscle tissue? A.Epicardium B.Pericardium C.Myocardium D.Endocardium E.Hypocardium

C. Myocardium

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

What of the following chambers of the heart contain deoxygenated blood? A.Left atrium and left ventricle B.Left atrium only C.Right atrium and right ventricle D.Right ventricle only E.Left atrium and right ventricle

C. Right atrium and right ventricle

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.

The outermost layer of the pericardium, which consists of inelastic dense irregular connective tissue, is called the A.parietal layer of pericardium. B.serous pericardium. C.fibrous pericardium. D.epicardium. E.endocardium.

C. fibrous pericardium.

Cardiac muscle fibers are electrically connected to neighboring fibers by A.desmosomes. B.tight junctions. C.gap junctions. D.interneurons. E.chordae tendinae.

C. gap junctions.

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

Blood leaving the left ventricle passes through which of the following structures? A.Right atrium B.Interventricular septum C.Bicuspid valve D.Aortic semilunar valve E.Pulmonary semilunar valve

D. Aortic semilunar valve

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

This is a network of specialized cardiac muscle fibers that provide a path for each cycle of cardiac excitation to progress through the heart. A.Systemic circuit B.Intercalated discs C.Cardiovascular center D.Cardiac conduction system E.Pulmonary circuit

D. Cardiac conduction system

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

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

This is used to reduce friction between the layers of membranes surrounding the heart. A.Synovial fluid B.Endocardium C.Pleural fluid D.Pericardial fluid E.Capillary endothelium

D. Pericardial fluid

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.Sinoatrial (SA) node, Purkinje fibers, AV node, Bundle of His C.Purkinje fibers, AV node, SA node, Bundle of His D.SA node, AV node, Bundle of His, Purkinje fibers E.Bundle of His, SA node, AV node, Purkinje fibers

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

The second heart sound (dupp) closely follows which of the events listed below? A.Valvular stenosis B.Semilunar valves opening C.Atrioventricular valves closing D.Semilunar valves closing E.Atrioventricular valves opening

D. Semilunar valves closing

This 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

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.

Which of the following chambers of the heart is surrounded by the thickest layer of myocardium? A.right atrium B.left atrium C.right ventricle D.left ventricle E.right auricle

D. left ventricle

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

During which of following periods does the largest volume of blood enter the arteries? A.atrial diastole B.ventricular diastole C.atrial systole D.ventricular systole

D. ventricular systole

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

Isovolumetric contraction is the phase of the cardiac cardiac cycle in which A.the semilunar valves are open. B.ventricular repolarization occurs. C.atrial depolarization occurs. D.oxygenated blood leaves the heart into the systemic circulation. E.ventricular pressure increases and ventricular volume remains the same.

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

Discuss the common nutrient sources used by cardiac muscle to produce ATP in a resting individual.

Model Short Answer: At rest, the heart relies exclusively on aerobic cellular respiration. At rest, the heart's ATP comes mainly from oxidation of fatty acids (60%), and glucose (35%) with smaller contributions from lactic acid, amino acids, and ketone bodies.

Briefly describe why cardiac tissue cannot repair itself after damage?

Model Short Answer: Cardiac muscle lacks stem cells and mature cardiac muscle fibers cannot go through mitosis.

Why is the myocardium of the left ventricle thicker than the myocardium of the right ventricle?

Model Short Answer: The left ventricle muscular wall is thicker than the right ventricle because it has to generate higher pressure to overcome the greater resistance of the longer systemic circulation route versus the shorter pulmonary circulation route.

Define arrhythmia and discuss different categories of arrhythmias.

Model Short Answer: The term arrhythmia or dysrhythmia refers to an abnormal rhythm as a result of a defect in the conduction system of the heart. Arrhythmias are categorized by their speed, rhythm, and origination of the problem. Bradycardia refers to a slow heart rate (blow 50 bpm); tachycardia refers to a rapid heart rate (over 100 bpm); and fibrillation refers to rapid, uncoordinated heartbeats. Arrhythmias that originate in the atria are called supraventricular or atrial arrhythmias; those that originate in the ventricles are called ventricular arrhythmias.

Explain how the heart pumps blood into two separate closed circuits that are arranged in series.

Model Short Answer: The two circuits are the pulmonary and systemic circuits.Venous blood from the systemic circulation enters the right atrium. The blood moves from the right atrium into the right ventricle of the heart, which pumps blood through the pulmonary circuit eventually filling the left atrium. The blood moves from the left atrium into the left ventricle of the heart, which pumps blood through the systemic circuit back into the right atrium.