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At what rate does the sinoatrial (SA) node depolarize?

75 times per minute

Which of the following structures collects the depolarization wave from the atria to pass it onto the ventricles? -AV node -atrioventricular bundle -bundle branches -SA node

AV node

Heart murmurs caused by a stenotic mitral valve ______. -are detected while blood flow into the left ventricle is reduced -are detected due to the turbulent blood flow that occurs as blood backflows into the left atrium -are detected if the valve's cusps are thin and flexible -All of the listed responses are true.

Are detected while blood flow into the left ventricle is reduced

Which of the following is NOT a difference between cardiac and skeletal muscle? -Cardiac muscle does not use the sliding filament mechanism for contraction; skeletal muscle does. -Cardiac muscle cells quickly die in the absence of oxygen; skeletal muscle cells are better able to adapt to oxygen deficiency. -The plasma membranes of cardiac muscle cells interlock, but skeletal muscle fibers are independent. -Cardiac muscle cells contain more mitochondria than do skeletal muscle cells.

Cardiac muscle does not use the sliding filament mechanism for contraction; skeletal muscle does

The right side of the heart is considered the systemic circuit pump. T/F?

False The right side of the heart pumps oxygen-poor blood to the lungs to be re-oxygenated. For this, the right side of the heart is considered the pulmonary circuit pump

The role of the chordae tendineae is to open the AV valves at the appropriate time. T/F?

False The role of the chordae tendineae is to anchor the AV valves against the large pressure changes that occur as the ventricles contract.

Why are gap junctions a vital part of the intercellular connection of cardiac muscles?

Gap junctions allow action potentials to spread to connected cells.

The order of impulse conduction in the heart, from beginning to end, is __________.

SA node, AV node, bundle of His, bundle branches, and Purkinje fibers

Adding a chemical that reduces Na+ transport near the sinoatrial (SA) node would have what effect on the heart's intrinsic conducting system?

The SA node would depolarize less quickly, reducing the heart rate.

Which description is INCORRECT for the layers of the heart and its serous membranes? - The fibrous pericardium prevents overfilling of the ventricles. - The endocardium is the deepest of the layers related to the heart. -The parietal pericardium is on the deep side of the fibrous pericardium. -The epicardium is also considered the parietal pericardium.

The epicardium is also considered the parietal pericardium.

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

The right ventricle empties into the pulmonary trunk

Blood enters the left and right coronary arteries directly from which vessel or chamber? -pulmonary trunk -aorta -circumflex artery -left ventricle

aorta

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

back pressure exerted by arterial blood

Which blood vessel carries blood from the anterior to the posterior of the heart? -left coronary artery -circumflex artery -marginal artery -posterior interventricular artery

circumflex artery

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

closure of the atrioventricular valves

Which of the following would increase cardiac output? -parasympathetic stimulation -high blood pressure -epinephrine -decreased calcium during contraction

epinephrine

What causes heart sounds? -heart valve closure -pressure of blood in the ventricles -opening of heart valves -blood flowing from the atria into the ventricles

heart valve closure

Which of the following is NOT a factor that increases stroke volume? -increasing afterload -increasing sympathetic stimulation -increasing preload -increasing contractility

increasing afterload

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

intercalated discs

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 ejection -ventricular filling -isovolumetric relaxation phase -isovolumetric contraction phase

isovolumetric contraction phase

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

left atrium

Failure in a particular chamber of the heart tends to cause a backup of blood in the lungs, known as pulmonary congestive heart failure. Failure of which chamber of the heart would lead to such a backup? -right ventricle -right atrium -left atrium -left ventricle

left ventricle

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

left ventricle

Which of these muscles is particularly associated with anchoring the right and left atrioventricular valves? myocardium pectinate muscles trabeculae carneae papillary muscles

papillary muscles

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

phase 2b

Which of the following descriptions does NOT describe atrioventricular (AV) valves? -flap-like -open based on pressure changes in the atria versus the ventricles -pocket-like -anchored inferiorly by specialized connective tissue

pocket-like

Which of the following is a branch of the right coronary artery? -coronary sinus -posterior interventricular artery -circumflex artery -anterior interventricular artery

posterior interventricular artery

As your muscles contract during activity, more blood is returned to the heart. Which variable would be affected and what would be the outcome of this action? -End-systolic volume would be increased, which would increase cardiac output. -Preload would be increased, which would increase cardiac output. -Contractility would be increased, which would increase cardiac output. -Afterload would increase, which would increase cardiac output.

preload would be increased, which would increase cardiac output

Hypercalcemia could cause ______. -increased osteoclast activity -prolonged T wave -hypersecretion of parathyroid hormone -All of the listed responses are correct

prolonged T wave

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

pulmonary veins

Which of these vessels returns blood to the left atrium of the heart? superior vena cava coronary sinus pulmonary veins pulmonary trunk

pulmonary veins

Which of the following terms is correctly matched to its description? -diastole: contraction period -stroke volume: amount of blood pumped out by each ventricle in one minute -quiescent period: total heart relaxation between heartbeats -systole: relaxed period

quiescent period: total heart relaxation between heartbeats

The presence of an incompetent tricuspid valve would have the direct effect of causing ______. -reduced efficiency in the delivery of blood to the lungs -reduced efficiency in the delivery of blood to the myocardium -reduced efficiency in the delivery of blood from the lungs to the heart -reduced efficiency in the delivery of blood from the head to the heart

reduced efficiency in the delivery of blood to the lungs

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

right atrium

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

right atrium

A blockage in which of these vessels could cause a myocardial infarction in the lateral right side of the heart? -right marginal artery -circumflex artery -anterior interventricular artery -posterior interventricular artery

right marginal artery

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? -subendocardial conducting network (Purkinje fibers) -sinoatrial (SA) node -interventricular septum -bundle branches

sinoatrial (SA) node

The anatomy of the intrinsic conduction system causes contraction of the ventricles to begin at the apex and move superiorly. Why is this important? -because the Purkinje fibers conduct action potentials away from the heart apex -so the atria can finish contracting before the ventricles contract -so blood is forced upward, toward the semilunar valves -because the AV bundle is the only electrical connection between the atria and the ventricles

so blood is forced upward, toward the semilunar valves

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

tricuspid

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

ventricular systole