Internal Structure of the Heart (Part 2)

In terms of size and shape, the human heart is about the size of a closed fist. It also lies to the left of the center. Hearts are responsible for pumping enough blood to supply a continuous supply of oxygen and nutrients to the brain and other vital organs.

As you take this quiz, you will be able to identify each part of the internal structure of the heart and its function to maintain the heart’s normal function.

  • Question of

    The outermost layer of the heart wall.

    • Epicardium
    • Fossa ovalis
    • Ventricle
    • Aorta

    Correct Wrong

    A layer of the heart wall called the epicardium surrounds the heart. Associated with the outer wall of the heart is the epicardium, which refers to both the outer layer and the inner layer of the serous visceral pericardium. Epicardium is a layer of connective tissue and fat that surrounds the heart and protects it from friction or trauma.

  • Question of

    This artery carries deoxygenated blood from the right ventricle to the lungs.

    • Pulmonary artery
    • Papillary muscles
    • Pulmonary veins
    • Inferior vena cava (or IVC)

    Correct Wrong

    From the right side of the heart, the pulmonary artery carries deoxygenated blood to the lungs. The main pulmonary artery starts as the pulmonary trunk, then divides into the right and left main pulmonary arteries.

  • Question of

    A flap-like valve between the left atrium and left ventricle of the heart.

    • Mitral valve
    • Aorta
    • Tricuspid valve
    • Pulmonary valve

    Correct Wrong

    Mitral valves, which are also known as bicuspid valves or left atrioventricular valves, are two flaps located between the left atrium and left ventricle. During ejection (systole), the mitral valve prevents blood from flowing back into the left atrium.

  • Question of

    There are parallel muscular ridges inside the atria of the heart.

    • Pectinate muscles
    • Superior vena cava
    • Pulmonary valve
    • Interventricular septum

    Correct Wrong

    The pectinate muscles of the heart are parallel muscular ridges found on the walls of the atria. Several sources suggest that pectinate muscles increase contraction strength without significantly increasing heart mass. Pectinate muscles are not the same as trabeculae carneae, which line the inner walls of both ventricles.

  • Question of

    It is one of two large chambers at the bottom of the heart.

    • Ventricle
    • Pulmonary artery
    • Interventricular septum
    • Chordae tendineae

    Correct Wrong

    There are two large chambers at the bottom of the heart called ventricles, which receive blood from the atrium and expel it. Right ventricle pumps blood into pulmonary circulation to the lungs. Left ventricle pumps blood into systemic circulation through aorta.

  • Question of

    The veins that transport oxygenated blood from the lungs to the heart.

    • Pulmonary veins
    • Tricuspid valve
    • Superior vena cava
    • Pulmonary valve

    Correct Wrong

    The pulmonary veins carry oxygenated blood from the lungs to the heart. The four largest pulmonary veins drain into the left atrium of the heart, two from each lung. They are part of the pulmonary circulation.

  • Question of

    The upper or receiving chamber of the heart that pumps blood into the lower chambers.

    • Atrium
    • Pulmonary veins
    • Pulmonary valve
    • Ventricle

    Correct Wrong

    (plural = atria) The atrium is the upper or receiving chamber of the heart, which pumps blood into the lower chambers just before contraction. In the right atrium, blood flows from the systemic circuit to the right ventricle. Hence, as blood flows from the pulmonary circuit into the left ventricle, it is received by the left atrium.

  • Question of

    This valve prevents blood from flowing backward into the right ventricle from the base of the pulmonary trunk. It has three flaps.

    • Pulmonary valve
    • Pulmonary veins
    • Inferior vena cava (or IVC)
    • Atrium

    Correct Wrong

    The pulmonary valve (also known as the pulmonary semilunar valve, the right semilunar valve, or pulmonic valve) prevents blood from flowing back into the right ventricle; consists of three flaps.

  • Question of

    The thickest layer of the heart is composed of cardiac muscle cells.

    • Myocardium
    • Inferior vena cava (or IVC)
    • Pulmonary valve
    • Endocardium

    Correct Wrong

    Myocardium comprises the cells of the cardiac muscle, blood vessels, and nerves that regulate the heartbeat. The rapid, involuntary contraction and relaxation of the cardiac muscle is essential for pumping blood throughout the cardiovascular system.

  • Question of

    Blood returns to the heart through a large vein in the superior portion of the body.

    • Superior vena cava
    • Inferior vena cava (or IVC)
    • Myocardium
    • Fossa ovalis

    Correct Wrong

    A large vein in the body, the superior vena cava returns deoxygenated blood from the body to the heart. It lies between the superior and middle mediastinum. The superior vena cava is responsible for returning venous blood from structures above the diaphragm.