Heart

Which of the following is not a function of the pericardium

• Protect and anchor the heart

• Allows the heart to work in a friction-free environment

• Maintain a reservoir of blood so that the heart can perfuse itself during diastole

• Prevent overfilling of the heart with blood

Where do the coronary arteries originate from?

• Left ventricle

• Aortic arch

• Ascending aorta

• Descending aorta

When are the coronary arteries filled with blood?

• Ventricular Systole

• Ventricular Diastole

• They maintain constant flow, as they receive pressure from the contraction of both atria and ventricles

• When the ventricles contract

Branches of the coronary veins converge at the

• Coronary sinus

• Inferior vena cava

• Superior vena cava

• Right atrium

Between the p wave and the q wave one should see a lack of deflection, indicating an isoelectric current that is moving neither towards nor away from the lead. Why is this?

• Following atrial contraction and before ventricular contraction, there is a period of isovolumetric contraction

• Skeletal fibers have greater electrical resistance, which slows down the current as it passes from the right atrium to the septum

• The AV node delays the electrical impulse by ~0.1 sec so that blood has time to enter the ventricles

• Without this period of isoelectric mediation by the vagus nerve, the SA node would speed up its rate of impulse generatiom

The T wave represents

• Ventricular repolarization

• Ventricular depolarization

• Atrial depolarization

• Atrial repolarization

Fall in ventricular pressure causes what first

• Blood from atria to rush in

• AV valves to open

• Semilumar valves to shut

• Atria fill with blood

Forcefulness of contraction of individual ventricular muscle fibers

• Preload

• Afterload

• Cardiac output

• Contractility

Which of the following does not affect stroke volume

• Preload

• Afterload

• Cardiac Reserve

• Contractility

An average person may have this at 4-5x their resting value, while one suffering from severe heart disease may not have this at all

• Cardiac Reserve

• Exertional Output

• Contractility

• End Diastolic Volume