The atria and ventricles act as two separate contractile units due to?

The atria should contract as a unit, & the ventricles should contract as a unit. This occurs because the impulse spreads so rapidly that all myocardial cells in the atria and ventricles, respectively, contract at about the same time. The impulse spreads rapidly through the ventricles because of the conducting system.

hello my name is kailey,

i think the answer is false i   hope this

a

explanation: