Mastering A&P II Chapter 18 - The Cardivasucalar System: The Heart

What is happening during the "pause" phase when the heart is resting (relaxing)? Ventricles are filling. Valves are closing. Atria are contracting. Ventricles are contracting.

What causes the abnormal swishing or whooshing sound that is heard as blood regurgitates back into an atrium from its associated ventricle? semilunar valve closure aortic recoil blood turbulence pulmonary trunk expansion

What separates the parietal and visceral pericardium? fibrous pericardium myocardium pericardial cavity epicardium

Which of the following is the innermost layer of the heart? endocardium parietal layer epicardium visceral layer

Which layer of the heart wall contracts and is composed primarily of cardiac muscle tissue? visceral layer of the serous pericardium epicardium endocardium myocardium

Which of these vessels returns blood to the left atrium of the heart? pulmonary veins coronary sinus superior vena cava pulmonary trunk The pulmonary veins transport oxygen-enriched blood from the lungs to the left atrium.

Which of these muscles is particularly associated with anchoring the right and left atrioventricular valves? pectinate muscles trabeculae carneae papillary muscles myocardium Papillary muscles contract to tense the right and left atrioventricular valves via the chordae tendineae just before ventricular systole.

The right atrioventricular valve prevents backflow of blood from the right ventricle into the __________. pulmonary trunk left atrium left ventricle right atrium

Which statement is correct regarding the ventricles? The left ventricle empties into the pulmonary circuit. The right ventricle empties into the pulmonary trunk. The left ventricle has a thinner wall than the right ventricle. The right ventricle forms a complete circle in cross section.

Which heart chamber receives oxygenated blood from the lungs? left ventricle right atrium left atrium right ventricle

The __________ valve is located between the right atrium and the right ventricle. mitral aortic semilunar tricuspid pulmonary semilunar

Which valve is located between the right atrium and ventricle? bicuspid valve mitral valve pulmonary semilunar valve tricuspid valve

Into which chamber of the heart do the superior vena cava, inferior vena cava, and coronary sinus return deoxygenated blood? right atrium left ventricle right ventricle left atrium

Which chamber of the heart sends oxygenated blood to the systemic circuit via the aorta? right ventricle left ventricle right atrium left atrium

Which of the following is a branch of the right coronary artery? Arterial and venous coronary circulation. posterior interventricular artery coronary sinus circumflex artery anterior interventricular artery

Which of the following does NOT deliver deoxygenated blood to the heart? pulmonary veins inferior vena cava superior vena cava coronary sinus

The right side of the heart is considered the systemic circuit pump. True False

Which statement regarding cardiac muscle structure is accurate? Myofibrils of cardiac muscle tissue vary in diameter and branch extensively. Cardiac cells are long, cylindrical, and multinucleate. Cardiac muscle cells are independent of one another both structurally and functionally. Cardiac cells possess few mitochondria.

Consider the following characteristics of the cells found in muscle tissue. Which feature is shared by both cardiac muscle and skeletal muscle? intercalated discs branched cells striations triads

What structures connect the individual heart muscle cells? chordae tendineae trabaculae carneae intercalated discs anastomoses

At what rate does the sinoatrial (SA) node depolarize? At what rate does the sinoatrial (SA) node depolarize? Pathways of action potential propagation during a cardiac cycle. 30 times per minute 40 times per minute 50 times per minute 75 times per minute

Specifically, what part of the intrinsic conduction system generates the original stimulus that reaches the atrioventricular (AV) node, allowing it to conduct impulses to the atrioventricular bundle? interventricular septum bundle branches sinoatrial (SA) node subendocardial conducting network (Purkinje fibers)

Which portion of the electrocardiogram represents the depolarization wave received by the atria from the sinoatrial (SA) node? Tracing of a typical electrocardiogram. S-T segment P wave T wave QRS complex

Determine which of the following electrocardiogram (ECG) tracings is missing P waves but is otherwise regular. ECG tracings showing normal and various abnormal rhythms. A B C D

What heart problem would be experienced by an individual whose ECG is seen at C? The atria are not pumping blood. The heart would pump with too much pressure (hypertension). The ventricles are not reaching systole in every cardiac cycle. The heart is not pumping any blood at all.

Determine which ECG shows a normal sinus rhythm. A B C D

The order of impulse conduction in the heart, from beginning to end, is __________. SA node, bundle branches, AV node, bundle of His, and Purkinje fibers SA node, AV node, bundle of His, bundle branches, and Purkinje fibers SA node, bundle of His, AV node, bundle branches, and Purkinje fibers SA node, bundle branches, bundle of His, AV node, and Purkinje fibers

The P wave on an electrocardiogram represents __________. ventricular repolarization atrial repolarization ventricular depolarization atrial depolarization

What does the QRS wave of the electrocardiogram (ECG) represent? atrial depolarizaton ventricular repolarization atrial repolarization ventricular depolarization

What is the period during the cardiac cycle when the ventricles are completely closed and blood volume in them remains constant as the ventricles contract? ventricular filling isovolumetric relaxation phase isovolumetric contraction phase ventricular ejection

At what point in the cardiac cycle is pressure in the ventricles the highest (around 120 mm Hg in the left ventricle)? At what point in the cardiac cycle is pressure in the ventricles the highest (around 120 mm Hg in the left ventricle)? Relationships between the ECG and left chamber pressures during the cardiac cycle. mid-to-late diastole (ventricular filling) ventricular systole mid-to-late diastole (atrial contraction) early diastole (isovolumetric relaxation)

During which of these stages are the pulmonary and aortic valves open? phase 1 phase 2a phase 2b phase 3

The first heart sound (the "lub" of the "lub-dup") is caused by __________. -opening of the atrioventricular valves -closure of the atrioventricular valves -opening of the semilunar valves -closure of the semilunar valves

What causes heart sounds? -opening of heart valves -cardiac muscle contraction -pressure of blood in the ventricles -heart valve closure

Which best describe the isovolumetric contraction phase of the cardiac cycle? The pressure from the atrial contractions opens the semilunar valves. As ventricular systole starts, the AV valves close, which immediately opens the semilunar valves. As ventricular systole start, the AV valves are closed and the semilunar valves are closed. Because the ventricles are contracting and both valves are closed, pressure increases rapidly leading to ejection. As pressure builds up in the ventricles during systole, the AV valves open and allow blood to leave the heart. This closed pressure system is important for the ventricles to be able to generate enough pressure to open the semilunar valves and eject blood from the heart.

Calculate the stroke volume if the end diastolic volume (EDV) is 135 mL and the end systolic volume (ESV) is 60 mL. 60 mL 75 mL 205 mL 8100 mL

Which of the following increases stroke volume? severe blood loss decrease in end diastolic volume (EDV) exercise decrease in preload

What best describes afterload? back pressure exerted by arterial blood degree of stretch of the heart muscle contractility of cardiac muscle cardiac reserve