Physiology and Pathophysiology: Cardiovascular System Lecture 7

Does parasympathetic stimulation have a negative effect on autorhythmicity?

Can the AV node become the pacemaker of the heart if the SA node fails?

Do action potentials occur in excitable cells such as cardiac muscle?

Is the SA node the normal pacemaker of the heart?

Is action potential of cardiac muscle known for its long duration?

Does sympathetic stimulation have a positive effect on autorhythmicity?

Does the depolarization of the membrane cause a large influx of sodium ions inside the cell?

Is the heart (cardiac muscle) characterized by automatic and rhythmic ability?

Does the heart have the ability to generate its own electric impulses and beat regularly?

Is the AV node a potential pacemaker of the heart if the SA node fails?

Hyperpolarization occurs due to the influx of anions (Cl– ions) through the chloride channels

Refractory period refers to the amount of time it takes for an excitable membrane to be ready to respond to a second stimulus

The cardiac electric impulse is generated from the autorhythmic cells in the AV node

The closing of sodium ion channels and opening of potassium ion channels leads to repolarization

Conductivity is the ability of the cardiac muscle to transmit action potential from one cell to the next through the conductive system

The cardiac electric impulse spreads to the right and left atria of the heart

The cardiac electric impulse passes in the AV node to reach the ventricles

Opening of voltage gated Ca+2 channels leads to contraction of cardiac muscle (systole)

The AV node allows the passage of the cardiac electric impulse slowly (AV nodal delay)

Contraction of the myocardial muscle (Diastole) is caused by the closing of sodium ion channels and opening of potassium ion channels