CH 20 Questions

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

closing the AV valves

The atrioventricular node is located in the right atrium, just inferior to the opening of the superior vena cava. inferior part of the interatrial septum. interventricular septum, near the heart base. walls of the ventricles, with the

inferior part of the interatrial septum

Which of the following statements is INCORRECT? The coronary sinus empties into the left atrium. Portions of the interior wall of the right atrium have pectinate muscles while the walls of the left atrium are smooth. The left atrium receives blood from 4 pulmonary veins. The left and right ventricles contain chordae tendineae and trabeculae carneae.

The coronary sinus empties into the left atrium.

Damage or dysfunction of the sinoatrial node does not result in cardiac failure because additional portions of the autorhythmic fibers can create action potentials. If a heart rate was measured at 30 beats/min, it may indicate that these fibers are creating spontaneous action potential in the heart. Purkinje fibers Bundle of His Both Bundle of His and Purkinje fibers Atrioventricular node

Both Bundle of His and Purkinje fibers

Which statement concerning the pulmonary arteries is FALSE? The right ventricle pumps blood into the pulmonary arteries. The pulmonary arteries carry oxygenated blood back from the lungs to the heart. The pulmonary arteries are part of the pulmonary circuit. The pulmonary arteries carry poorly oxygenated blood

False: The pulmonary arteries carry oxygenated blood back from the lungs to the heart. The pulmonary veins carry oxygenated blood back to the heart from the lungs. Arteries bring blood AWAY the heart.

Oxygen-Rich Blood Returning to the Heart

Lungs > Lung Capillaries > Pulmonary Veins > Left Atrium > Mitral/Bicuspid Valve > Left Ventricle > Aortic/semilunar Valve > Aorta

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

all four valves are closed

An electrocardiogram can help determine all of the following except: a cause of chest pain if a heart attack has occurred if the heart has enlarged if the conduction pathway is functioning normally all of these choices can be determined during an ECG

all of these

Stroke volume is regulated by: Preload Contractility of the individual ventricular muscle fibers Afterload or the pressure that must be exceeded before ejection of blood from the ventricles can occur All of these regulate stroke volume

all of these

Which of the following statements is/are correct? Valves open and close in response to pressure changes The chordae tendineae and papillary muscles stop the atrioventricular valves from everting in response to high ventricular pressure. The semilunar valves are closed by filling of cusps by backflow of blood.

all of these are correct

The P-wave in an electrocardiogram occurs during atrial depolarization. ventricular depolarization. ventricular repolarization. atrial repolarization.

atrial depolarization

Cardiac muscle cells (fibers) that do not contract but instead create and conduct the action potential throughout the heart are atrial fibers. contractile fibers. autorhythmic fibers. ventricular fibers.

autorhythmic fibers.

Which of the following are NOT part of the conducting system in the heart? atrioventricular (AV) valve Purkinje fibers internodal bundles sinoatrial (SA) node

av valve

When the ventricles relax, intraventricular pressure falls and __________.

blood is pushed against the semilunar valves, causing them to close

The term that describes the relaxation of a heart chamber wall as it fills with blood is__________ .

diastole

The auricles are

earlike flaps on the atria

Which layer of the heart wall is visceral pericardium? epicardium endothelium myocardium endocardium

epicardium

The AV node acts as a natural pacemaker for the heart.

false

The left ventricle is not as thick as the right ventricle since the right ventricle pumps blood throughout the body.

false

The left ventricular pressure must be greater than the aortic pressure during ventricular ejection so that blood will move out through the pulmonary arteries. True False

false

The tricuspid valve is also known as the mitral valve.

false

Atrial systole is necessary to fill the aortas with blood allow blood to passively fill the chambers fill the ventricles with blood close the AV valves

fill the ventricles with blood

During ventricular systole, blood is forced from the ventricles into the aorta and pulmonary trunk. forced from the atria into the ventricles. not flowing into or out of the heart. flowing from the systemic and pulmonary circuits into both the atria and ventricles.

forced from the atria into the ventricles.

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

outer layer of heart

Which structure anchors the chordae tendinae of the atrioventricular valves? papillary muscle trabeculae carnea interventricular septum pectinate muscle

papillary muscle

Which of the following vessels does not carry oxygen-poor blood to the heart? the pulmonary vein the coronary sinus the inferior vena cava the superior vena cava

pulmonary

The right side of the heart is concerned with two of the choices are correct pulmonary circulation systemic circulation pumping oxygenated blood

pulmonary circulation

Which vessel carries oxygenated blood? pulmonary trunk pulmonary vein superior vena cava pulmonary artery

pulmonary vein

Comparatively, which phase is the longest during an action potential in a ventricular contractile fiber? refractory depolarization contraction repolarization

refractory

Which heart chamber has the thickest myocardium?

the left ventricle, because it pumps blood at a higher pressure

A normal resting stroke volume is around 70-mL.

true

Cardiac cells are also auto rhythmic. This means that they are self-excitatory and can generate their own action potentials.

true

Cardiac cells are connective, which means that they can transfer actions potentials from one cell to the next via gap junctions.

true

Cardiac output equals the stroke volume multiplied by the heart rate.

true

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

true

The right atrium receives blood from the superior and inferior vena cava and the coronary sinus while the left atrium receives blood from the 4 pulmonary veins. 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

The sympathetic impulses increase heart rate and contraction force while parasympathetic impulses decrease heart rate. 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

The semilunar valves prevent backflow of blood into the _____. ventricles vena cavae lungs atria

ventricles

If the stroke volume (mL of blood leaving the left ventricle during each contraction) is 70mL and the SA node is functioning properly, how much blood is being ejected from the left ventricle each minute? 3.5 L/min 0.7 L/min 2.1 L/min 4.9 L/min

4.9

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

QRS

Which of the following ECG waves represents Ventricular excitation/depolarization? P QRS T Q

QRS

Which of the following is the correct pathway for passage of a drop of blood through the heart? Right atrium, tricuspid valve, right ventricle, pulmonary semilunar valve, pulmonary artery, lungs, pulmonary veins, left atrium, bicuspid valve, left ventricle, aortic semilunar valve. Right atrium, tricuspid valve, right ventricle, pulmonary semilunar valve, pulmonary veins, lungs, pulmonary artery, left atrium, bicuspid valve, left ventricle, aortic semilunar valve. Right atrium, bicuspid valve, right ventricle, pulmonary semilunar valve, pulmonary artery, lungs, pulmonary veins, left atrium, tricuspid valve, left ventricle, aortic semilunar valve. Right atrium, tricuspid valve, right ventricle, pulmonary semilunar valve, pulmonary artery, lungs, pulmonary veins, left atrium, bicuspid valve, left ventricle, pulmonary semilunar valve.

Right atrium, tricuspid valve, right ventricle, pulmonary semilunar valve, pulmonary artery, lungs, pulmonary veins, left atrium, bicuspid valve, left ventricle, aortic semilunar valve.

Semilunar valves are located between the great veins and the atria. only between the left ventricle and the aorta. between the ventricles and the great arteries. between the atria and the ventricles

btw ventricles and great areteries

The amount of blood ejected from either ventricle every minute is called: stroke volume end-diastolic volume afterload cardiac output heart rate

cardiac output

the fibrous skeleton of the heart functions in all of these ways EXCEPT in __________. lining the heart chambers, covering the heart valves, and forming the ridge of the crista terminalis causing direct spread of electrical impulses from the atria to the ventricles anchoring the valve cusps preventing overdilation of the valve openings acting as the point of insertion for bundles of cardiac muscle in the atria and ventricles

causing direct spread of electrical impulses from the atria to the ventricles

Which vessel returns most of the venous blood from the heart to the right atrium? the coronary sinus the anterior cardiac vein the great cardiac vein the posterior interventricular vein

coronary sinus

Which structures permit action potentials in the autorhythmic cardiac fibers to move from one cell immediately to an adjacent cell? gap junction desmosomes intercalated disc tight junctions

gap junction

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

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

Towards the end of ventricular systole when ventricular blood pressure exceeds aortic blood pressure semilunar valves close semilunar valves open AV valves close AV valves open

semilunar valves open

Semilunar valves function to prevent blood from flowing back into the ventricles during ventricular diastole atria during atrial diastole ventricles during ventricular systole atria during atrial systole

ventricles during ventricular diastole

Blood leaves the heart during isovolumetric ventricular relaxation ventricular ejection ventricular relaxation passive ventricular filling

ventricular ejection

The__________ layer of the serous pericardium is also known as the epicardium.

visceral