Purkinje Fibers actually makes the ventricles contract.
There are no valves between the atria. The valves between the atria and ventricles close when the ventricles contract.
The ventricles contract.
When relaxed, the atria expand, and then the ventricles contract.
Not really sure what you mean by the base, the ventricles contract from the Apex (which is at the bottom) upwards.
The pulmonary artery and the aorta lead upward and away from the ventricles. Since the ventricles contract from the bottom, blood is more efficiently pushed out of the heart.
Yes, atria contracts before the ventricles.
Systole
After the blood pumps from the atria to the ventricles, during systole.Systole
Into the heart
contract
The right ventricle pumps blood to the lungs.
The ventricles contract to pump blood out of the heart.