Chapter 13: Cardiac Muscle and Cardiovascular System

These flashcards cover key concepts related to cardiac muscle, the cardiovascular system, and electrical/mechanical components of the heart.

The two types of cardiac muscle are cells and cells.

pacemaker cells; contractile cells

The cardiovascular system consists of the heart, blood vessels, and __.

blood

The cardiac cycle refers to the __ component of the heart.

mechanical

The electrical component of the heart influences the __ of the heart.

rate

Skeletal muscle requires __ input to function, while cardiac muscle does not.

neural

The amount of blood being ejected by the heart is referred to as __ output.

cardiac

Pacemaker cells generate __ action potentials spontaneously.

action

The pacemaker potential is primarily driven by __ influx through funny channels.

sodium

The calcium influx that contributes to depolarization in pacemaker cells is through __ channels.

L-type calcium

The resting membrane potential of pacemaker cells is typically around __ mV.

-70

During isovolumetric contraction, all heart valves are __.

closed

The heart sound 'lub' corresponds to the closure of __ valves.

AV (atrioventricular)

The formula for cardiac output (CO) is CO = x .

heart rate (HR); stroke volume (SV)

Norepinephrine released by the sympathetic division increases heart rate by acting on __ receptors.

beta-1 (β1)

The preload is determined by the volume of blood in the ventricles at the end of __.

diastole

The afterload is the amount of pressure the heart must overcome to eject blood into the __.

aorta

The T wave on an EKG represents __ repolarization.

ventricular

In pacemaker cells, the rapid depolarization phase is mediated by a massive influx of __.

calcium

During the cardiac cycle, __ refers to the contraction phase of the heart.

systole

The electrical signals from the heart can be monitored via an __.

EKG (electrocardiogram)