chapter 24

• __________ are primarily responsible for the pacemaker potential seen in pacemaker cells.

• • Leaky sodium channels

• Voltage gated chloride channels

• norepinephrine channels

• epinephrine channels

____ cells produce mechanical force that moves blood

• cardiac contractile

• conduction fiber

• pacemaker

• autorhythmic

what are the periods of heart events?

• I. ISOVOLUMETRIC CONTRACTION, II. VENTRICULAR FILLING, III. VENTRICULAR EJECTION IV. ISOVOLUMETRIC RELAXATION

• I. VENTRICULAR FILLING, II. ISOVOLUMETRIC CONTRACTION, III. VENTRICULAR EJECTION IV. ISOVOLUMETRIC RELAXATION

• I. ISOVOLUMETRIC RELAXATION, II. ISOVOLUMETRIC CONTRACTION III. VENTRICULAR EJECTION IV. VENTRICULAR FILLING

Contractility is _______ affected by EDV.

• positively

• negatively

____ activity has a positive effect on filling time.

• CIC

• CAC

The ___ becomes more active when there is a lower-than-normal frequency of impulse conduction from baroreceptors.

• CAC

• CIC

Starling’s law of the heart relates more to

• stroke volume than to heart rate.

• preload than to afterload

• CIC than to CAC

____ has a positive effect on the amount of force that a ventricle must exert to cause blood ejection.

• preload

• afterload

3 ways to decrease ESV include

• decrease afterload

• increase preload

• decrease preload

• increase contractility

you can increase EDV by:

• increasing venous return

• decreasing venous return

• increase filling time

• decrease filling time