Heart

The following is a list of vessels and structures that are associated with the heart. 1. right atrium 2. left atrium 3. right ventricle 4. left ventricle 5. venae cavae 6. aorta 7. pulmonary trunk 8. pulmonary veins What is the correct order for the flow of blood entering from the systemic circulation?

5, 1, 3, 7, 8, 2, 4, 6

The first heart sound is heard when the

AV valves close.

Which parts of the following statement are true? The AV node delivers the stimulus to the AV bundle, located within the interventricular septum.

Both parts of the statement are true.

Define cardiac cycle. (Module 18.9A)

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

Which structures collect blood from the myocardium, and into which heart chamber does this blood flow? (Module 18.4B)

Coronary veins collect blood from the myocardium and carry it to the right atrium.

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.

List the important features of the ECG, and indicate what each represents. (Module 18.13B)

P wave (atrial depolarization), QRS complex (ventricular depolarization), T wave (ventricular repolarization)

Compare the anterior cardiac veins to the posterior vein of the left ventricle. (Module 18.5B)

The anterior cardiac veins drain the anterior surface of the right ventricle and empty into the right atrium; the posterior vein of left ventricle drains the area supplied by the circumflex artery (posterior surface of the left ventricle).

Comparing the left ventricle with the right ventricle, which of the following is true?

The left ventricle does more work than the right ventricle.

Why is the left ventricle more muscular than the right ventricle? (Module 18.6A)

The left ventricle must generate enough force to propel blood through the systemic circuit, whereas the right ventricle must generate only enough force to propel blood the short distance from the heart to the lungs in the pulmonary circuit.

Define mediastinum. (Module 18.2A)

The mediastinum is the region between the two pleural cavities that contains the heart, along with the great vessels, thymus, esophagus, and trachea.

both AV valves open and diastolic refilling begins

What occurs at the area labeled "D" on the graph?

Which of the following descriptions matches the phrase "near the left fifth intercostal space"?

apex of heart

The contraction phase of the upper chambers of the heart is called

atrial systole.

The earlike extension of the atrium is the

auricle

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

base.

A slower-than-normal heart rate is called

bradycardia.

Most of the middle layer in the heart wall is composed of

cardiac muscle cells.

The cusps (leaflets) of atrioventricular valves attach directly to

chordae tendineae.

The great and middle cardiac veins drain blood into the

coronary sinus.

Drugs that block the beta-one adrenergic receptors will

decrease heart rate.

Drugs known as calcium channel blockers such as nifedipine can be used to

decrease the force of cardiac contraction.

Cardiac output can be increased by all of the following except

decreasing ejection fraction.

The P wave of the electrocardiogram is a signal from

depolarization of the atria.

Arteriosclerosis can lead to all of the following except

diabetes.

What are the two phases of ventricular systole? (Module 18.10B)

isovolumetric contraction and ventricular ejection

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

left atrium, left ventricle, right atrium, right ventricle

Heart rate is controlled by neurons of the cardiovascular center located in the

medulla oblongata.

When the semilunar valves close, the AV valves then

open.

The cavity that contains only the heart is the

pericardial cavity.

List the three stages of an action potential in a cardiac muscle cell. (Module 18.11B)

rapid depolarization, plateau, and repolarization

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

right atrium.

The pulmonary semilunar valve prevents backward flow into the

right ventricle.

The volume of blood ejected from each ventricle during a contraction is called the

stroke volume.

During the cardiac cycle,

the QRS complex of the ECG precedes the increase in ventricular pressure.

Blood is supplied to the myocardium by

the coronary arteries.

Which of the following is greater during left ventricular systole?

the peak pressure in the ventricle

The normal pacemaker of the heart is located in

the sinoatrial node.

Blood flowing into the heart from the venae cavae flows next through the ________ valve.

tricuspid

An equivalent term for epicardium is

visceral pericardium.

The long plateau phase of the cardiac muscle action potential is due to

voltage-gated calcium channels remaining open.