Question 1

Which of the following is a sling-like structure that supports the heart?&#10;A) endocardium&#10;B) epicardium&#10;C) pericardium&#10;D) myocardium

Accepted Answer

Myocardial fibers are striated and interconnected in a way that encourages the rapid spread of the electrical signal over the myocardium and a well-coordinated and forceful muscle contraction.

Question 2

This term includes the venae cavae, pulmonary artery, pulmonary veins, and aorta.&#10;A) the great vessels&#10;B) the inferior chamber&#10;C) the angina pectoris&#10;D) the base

Accepted Answer

The large blood vessels attached to the heart are called the great vessels. They include the superior and inferior venae cavae, pulmonary trunk, four pulmonary veins, and the aorta.

Question 3

Which chamber of the heart works the hardest?&#10;A) right atrium&#10;B) left atrium&#10;C) right ventricle&#10;D) left ventricle

Accepted Answer

The left ventricular myocardium is thicker than the right ventricular myocardium. This difference is the result of the greater amount of force required to pump blood into the systemic circulation (aorta).

Question 4

Oxygenated blood is found in which structure?&#10;A) right ventricle&#10;B) right atrium&#10;C) pulmonary artery&#10;D) pulmonary veins

Accepted Answer

The oxygenated blood flows through four pulmonary veins from the lungs into the left atrium.

Question 5

What is the cause of the heart sounds &#34;lubb-dupp?&#34;&#10;A) vibrations caused by closure of valves&#10;B) firing of the sinoatrial (SA) node&#10;C) movement of blood through the valves&#10;D) flow of blood through the coronary vessels

Accepted Answer

The heart sounds ("lubb-dupp, lubb-dupp") are made by the vibrations caused by the closure of the valves.

Question 6

The mitral valve is:&#10;A) a semilunar valve that sees oxygenated blood.&#10;B) the right atrioventricular (AV) valve.&#10;C) a cuspid valve.&#10;D) a tricuspid valve.

Accepted Answer

The left AV valve is called the bicuspid valve because it has two cusps. It is also known as the mitral valve because it resembles a bishop's mitre-a hat with two cusps or flaps.

Question 7

Which of the following is responsible for the opening and closing of heart valves?&#10;A) oxygen saturation of the blood in the heart chambers&#10;B) hematocrit (HCT)&#10;C) pressure within the heart chambers&#10;D) tugging on the cusps

Accepted Answer

When the left ventricle relaxes, the valve is in a closed position. The semilunar valves close when the pressure in the pulmonary trunk and the aorta becomes greater than the pressure in the relaxed ventricles.

Question 8

Blood flows from the vena cava to the pulmonary artery. Which structure is not included in this blood path?&#10;A) right ventricle&#10;B) tricuspid valve&#10;C) pulmonic semilunar valve&#10;D) pulmonary veins

Accepted Answer

Pulmonary veins are not included in this blood path.

Question 9

Which structure is considered the pacemaker of the heart?&#10;A) the SA node&#10;B) the AV node&#10;C) the atrial conducting fibers&#10;D) the Purkinje fibers

Accepted Answer

Because the firing of the SA node sets the rate at which the heart beats, or contracts and relaxes, the SA node is called the pacemaker of the heart.

Question 10

The Purkinje fibers:&#10;A) send electrical signals to the bundle of His.&#10;B) are rapid conduction fibers that supply the ventricular myocardium.&#10;C) are the specialized cells of the SA node.&#10;D) are responsible for the P wave (ECG).

Accepted Answer

Purkinje fibers are distributed throughout the ventricular myocardium. Purkinje fibers conduct the cardiac impulse very rapidly throughout the ventricles, thereby ensuring a coordinated contraction of both ventricles.

Deck 16: Anatomy of the Heart