Exam
Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
The fact that the left ventricle of the heart is thicker than the right ventricle reveals that it ________.
expands the thoracic cage
pumps a greater volume of blood
sends blood through a smaller valve
pumps blood against a greater resistance
If the length of the absolute refractory period in cardiac muscle cells was the same as it is for
skeletal muscle cells, ________.
it would be less than 12 m
tetanic contractions might occur, which would stop the heart’s pumping action
it would be much longer before cardiac cells could respond to a second stimulation
contractions would last as long as the refractory period
Select the correct statement about cardiac output.
If a semilunar valve were partially obstructed, the end systolic volume in the affected
ventricle would be decreased.
Stroke volume increases if end diastolic volume decreases.
A slow heart rate increases end diastolic volume, stroke volume, and force of contraction.
Decreased venous return will result in increased end diastolic volume.
Damage to the ________ is referred to as heart block.