cardiovascular physiology

Unless there is an influence on a cardiac muscle cell, it will depolarize approximately ________ times a minute.

• 100

• 80

• 50

• 30

All the statements concerning intrinsic conduction system cell depolarization are true except

• they have a more negative resting membrane potential than the individual muscle cells.

• they open rapid calcium channels to speed up repolarization.

• they open fast sodium channels to make sure they depolarize rapidly.

• they prevent potassium leakage from the cell in order to deolarize faster.

The primary reason humans have a heart is

• to create adequate filtration.

• to increase intestinal absorption.

• to inhibit diffusion of nitrogenous wastes.

• to create adequate oncotic pressure.

The best definition of an artery is it

• carries blood away from the heart.

• carries blood to the heart.

• has oxygenated blood.

• has deoxygenated blood.

The right ventricle sends blood to the

• pulmonary trunk

• aorta

• pulmonary artery

• pulmonary vein

The heart valves are all closed during

• isovolumetric contraction.

• atrial systole.

• absolute refractory period.

• ventricular ejection.

The heart valves are all closed during

• isovolumetric relaxation

• atrial systole.

• absolute refractory period.

• ventricular ejection.

The right atrio-ventricuilar valve

• prevents blood from returning to the right atrium.

• prevents blood from returning to the left atrium.

• prevents blood from returning to the right ventricle.

• prevents blood from returning to the left ventricle.

The left semilunar valve

• prevents blood from returning to the right atrium.

• prevents blood from returning to the left atrium.

• prevents blood from returning to the right ventricle.

• prevents blood from returning to the left ventricle.

All the statements concerning cardiac muscle cells are true except

• they are individual cells held together by desmosomes.

• they depolarize by allowing sodium to flow into the cell through a gap junction.

• they are connected to an intrinsic conduction system.

• they have fast calcium channels to contract quickly.