ch 18 la

Which heart chamber receives blood from the lungs?

left atrium

What superficial landmark identifies the boundary between the left and right ventricles?

anterior interventricular sulcus

The function of the atrium is to

collect blood and pump blood to the ventricle.

The normal pacemaker of the heart is located in

the sinoatrial node.

What occurs at "B" on the graph?

semilunar valve closes

Define heart failure. (Module 18.16A)

Heart failure is a condition where the heart can no longer meet the oxygen and nutrient demands of peripheral tissues.

The right ventricle pumps blood to the

right and left lungs

Which part of the conduction system initiates the depolarizing impulse, which spreads throughout the heart?

SA node

What does the ECG wave tracing represent?

electrical activity in the heart

What does the QRS complex represent in the ECG wave tracing?

ventricular depolarization

Contraction of the atria results from which wave of depolarization on the ECG tracing?

P wave

Which part of the intrinsic conduction system delays the impulse briefly before it moves on to the ventricles?

AV node

The T wave on an ECG tracing represents

ventricular repolarization

A slower-than-normal heart rate is called

bradycardia.

Why does tetany not occur in cardiac muscle? (Module 18.11A)

Tetany does not occur because cardiac muscle has a long refractory period that continues until relaxation is well under way so summation cannot occur, and thus tetany cannot occur.

Give the alternate terms for heart contraction and heart relaxation. (Module 18.9B)

The alternate term for heart contraction is systole and the alternate term for heart relaxation is diastole.

Define cardiac cycle. (Module 18.9A)

Cardiac cycle is the period between the start of one heartbeat and the beginning of the next.

Blood is supplied to the myocardium by

the coronary arteries.

The ________ deliver(s) blood to the myocardium.

right coronary artery and left coronary artery

The heart is actually (one, two, or three) pumps?

two pumps

Which chamber receives blood from the superior and inferior venae cavae?

right atrium

Which heart chamber receives blood from the pulmonary veins?

left atrium

Which heart chamber pumps oxygen-poor blood out the pulmonary trunk?

right ventricle

Which chamber pumps oxygenated blood out the aorta to the systemic circuit?

left ventricle

The ________ has a greater workload than the ________.

left ventricle; right ventricle

The first heart sound ("lubb") is associated with

closing of the mitral valve.

The pulmonary arteries carry blood to the

lungs.

The pulmonary semilunar valve prevents backward flow into the

right ventricle.

The ________ separate(s) the two ventricles.

interventricular septum

Identify the most muscular chamber.

Left ventricle

Name the inner lining of the heart.

Endocardium

Identify the valve found between the left atrium and left ventricle.

Bicuspid (mitral) valve

What heart chamber pushes blood through the aortic semilunar valve?

Left ventricle

Name the irregular ridges of muscle lining the ventricles that are not indirectly connected to the atrioventricular valves.

Trabeculae carneae

What fibrous structure functions to anchor the atrioventricular valves in a closed position?

Chordae tendineae

Blood on the right never mixes with blood on the left, once the heart is fully developed.

True

At a heart rate of 60 beats/minute, a cardiac cycle lasts

1 second.

________ is to contraction as ________ is to relaxation.

Systole; diastole

Name the ridged bundles of muscle found projecting inside the right atrium.

Pectinate muscles

Identify the right atrioventricular valve.

Tricuspid valve

Identfiy the valve located at the exit of the right ventricle.

Pulmonary semilunar valve

The moderator band is found on both the right and left side of the heart.

False

Oxygenated blood flows through the right side of the heart.

False

The portion of the tracing of an electrocardiogram, ECG, that represents ventricular depolarization is the __________.

QRS complex

What is the function of the coronary circulation?

Provide a blood supply to the heart

What is the ligamentum arteriosum?

A remnant of the ductus arteriosus

Which chamber of the heart exits into the pulmonary trunk?

Right ventricle

Identify the ear like flaps that are attached to the top chambers of the heart.

Auricle

The first branch off the arch of the aorta is the brachiocephalic artery in both the sheep and the human.

True

The base of the heart is located at the bottom of the heart.

False

List the phases of the cardiac cycle. (Module 18.10A)

atrial systole, atrial diastole, ventricular systole, ventricular diastole

The pulmonary veins carry blood to the

heart.

Which of the following does NOT contribute to the partial or complete blockage of the coronary arteries that causes coronary ischemia?

a stent

The left ventricle pumps blood to the

aorta.

Name the four chambers of the heart. (Module 18.1C)

left atrium, left ventricle, right atrium, right ventricle

A faster-than-normal heart rate is called

tachycardia

The superior portion of the heart where major blood vessels enter and exit is the

base.

Blood returning to the heart from the pulmonary circuit first enters the

left atrium.

Define autorhythmicity. (Module 18.12A)

Autorhythmicity is the ability of the heart to contract without neural or hormonal stimulation.

Blood returning to the heart from the systemic circuit first enters the

right atrium.

Which part of the intrinsic conduction system normally initiates the depolarizing impulse that causes a heartbeat?

SA node

Which of these structures conduct(s) action potentials the slowest?

AV node

Why is ventricular fibrillation fatal? (Module 18.13C)

Ventricular fibrillation is fatal because the ventricles quiver and do not pump blood to the systemic circulation.

Which pathology is described as a thickening and toughening of arterial walls?

arteriosclerosis

The inferior point of the heart is called the

apex.

Coronary veins empty into the

right atrium.

The ________ valve prevents backward flow into the left atrium.

bicuspid

What occurs at "A" on the graph?

aortic semilunar valve opens

The heart beats approximately ________ times each day.

100,000

There are ________ pulmonary veins

4

Compared to the right ventricle, the left ventricle has all the following characteristics except that it

pumps a greater volume.

The heart pumps approximately ________ milliliters of blood each minute

6,000

________ is to slow heart rate as ________ is to fast heart rate.

Bradycardia; tachycardia

The first blood vessels to branch from the aorta are the ________ arteries.

coronary