DSM Section 17.4-17.5
Calculate the end-systolic volume (ESV) if the end-diastolic volume (EDV) is a resting heart is 110 ml and stroke volume (SV) is 70 ml.
40 ml
Approximately how much blood is pumped from each ventricle during the ventricular ejection phase?
70 ml
What percentage of atria blood flows passively into the ventricles?
80%
According to the Frank-Starling law, a bigger broad will result in ________.
A stronger contraction
Which of the following chemical messengers decreases heart rate?
Acetolcholine
Which of the following terms refers to the force the ventricles must overcome to eject blood into their respective arteries?
Afterload
Which of the following events is not part of the cardiac cycle?
Atrial contraction phase
Which hormone decreases cardiac output by decreasing blood volume and preload?
Atrial natriuretic peptide
Which of the following hormones decreased cardiac output by decreasing blood volume and preload?
Atrial natriuretic peptide
Which of the following events can be heard most easily with a stethoscope?
Closing of the atrioventricular valves
Inotropic agents affect ________.
Contractility
What largely determines preload?
End-diastolic volume (EDV)
Which of the following factors would increase cardiac output to the greatest extent?
Increased heart rate and increased stroke volume
During what phase is the S1 heart sound first heard?
Isovolumetric contraction phase
Which chamber generates the highest pressure during systole?
Left ventricle
Which wave on the electrocardiogram (ECG) corresponds with the ventricular filling phase of the cardiac cycle?
P wave
The degree of stretch experienced by the sarcomeres in the ventricle cells before they contract is called ________.
Preload
Which of the following paths does an action potential in the heart normally take?
SA node, atrial contractile calls. AV node where it is delayed, AV bundle, right and left bundle branches, Purkinje fibers, ventricular contractile cells
What is the volume of blood pumped out by one ventricle per heart beat?
Stroke volume (SV)
What two values are needed to calculate cardiac output (CO) for a ventricle?
Stroke volume (SV) and heart rate (HR)
Which cranial nerves have a negative chronotropic effect on heart rate?
Vagus nerves (CN X)
High-pressured blood in the ventricles ________.
forces the semilunar valves open