41.The cardiac output equal to
a.(EDV - ESV) x HR
b.heart rate : 1417115
41.The cardiac output is equal to
a.(EDV - ESV) x HR
b.heart rate x EDV
c.the difference between the stroke volume at rest and the stroke volume during exercise
d.the stroke volume minus the ESV
e.heart rate x blood pressure
42.Which factor(s) would decrease cardiac output?
a.increased venous return
b.decreased vagal stimulation of the heart
e.Both a and c
43.If the connection between the SA node and AV node becomes blocked,
a.the QRS complex will be absent on an ECG
b.the ventricles will beat more slowly
c.the atria will beat slower
d.tachycardia will occur
e.both a and d will occur
44.Which is true when your sympathetic nervous system is more active?
a.The SA node depolarizes more rapidly.
b.The myocardium repolarizes more frequently during one minute.
c.More Ca2+ becomes available and causes more forceful heart contractions.
d.Norepinephrine is stimulating the heart.
e.All of the above are true.
45.Which of the following leads to a decrease in ESV?
46.What percentage of ventricular filling is normally accomplished before atrial contraction begins?
47.Vagal influences on the heart result in
a.enhanced calcium permeability at the SA node
b.enhanced potassium permeability at the SA node
c.less frequent depolarization of the SA node
d.both a and b
e.both b and c
48.A condition in which the heart is contracting in an uncontrolled, rapid, and irregular manner
a.is heart block
c.can be treated with administration of an electrical current
d.is none of the above
e.is both b and c
49.The heart is
a.sympathetically innervated via cardiac nerve fibers
b.parasympathetically innervated by vagus nerve fibers
c.only partly innervated by the somatic nervous system
d.innervated by only the sympathetic division of the autonomic nervous system
e.both a and b
50.When the heart is sympathetically stimulated,
a.ESV will likely decrease
b.it is responding to acetylcholine
c.the fibrous skeleton of the heart is depolarizing
d.its stroke volume will decrease
e.all except c will occur