When relaxed, the atria expand, and then the ventricles contract.
they are in the heart of humans only
At diastole the muscles of the atria and ventricles relax and blood flows into the heart. Therefore the atria and ventricles and at rest together during diastole.
The ventricles relax during diastole.
Diastole is when the muscles of the atria and ventricles relax and blood flows into the heart.Ventricular diastole is when the muscles of the ventricles relax and blood flows into the heart. N.B It is called ventricular diastole and not ventrical diastole.
When relaxation or diastole is occurring in the atria blood flows through the atria and the AV valves into the ventricles. When contraction or systole is occurring in the atria the remaining blood that doesn't flow through during relaxation is pushed into the ventricles. As the atria relax, the ventricles begin contracting; ventricular pressure rises, closing the AV valves. Ventricular pressure continues rising until it exceeds the pressure in the large arteries stemming from the ventricles. The SL valves are forced open and blood is expelled from the ventricles into the aorta and pulmonary trunk. During this phase the ventricles relax because the blood is no longer compressed in their chambers. Blood expelled into the aorta and pulmonary trunk backflows toward the heart, which then closes the SL valves. During the ventricle contraction the atria stays in relaxation, filling with blood and when blood pressure on the atrial side of the AV valves exceeds that in the ventricles, the AV valves are forced open and ventricular filling begin all over again.
No, the tricuspid valve does not open during ventricular contraction. During this phase, known as systole, the ventricles contract to pump blood out of the heart, which causes the pressure in the ventricles to rise and forces the tricuspid valve to close. This closure prevents backflow of blood into the right atrium. The tricuspid valve opens during diastole, when the ventricles relax and blood flows from the atria into the ventricles.
diastole.systolic to diastolicThe ventricles relax during diastole
The cardiac cycle consists of five phases: 1) Atrial Systole, where the atria contract to fill the ventricles with blood; 2) Ventricular Systole, during which the ventricles contract to pump blood into the aorta and pulmonary artery; 3) Isovolumetric Contraction, where the ventricles contract without changing volume as the valves close; 4) Ventricular Diastole, when the ventricles relax and fill with blood; and 5) Atrial Diastole, where the atria relax and fill with blood returning from the body and lungs. This cycle ensures efficient blood circulation throughout the body.
the asnwer is t wave
Cardiac Muscle or myocardium are the muscle that make up the heart that contract and relax to pump blood.
The transmission delay at the AV node in the heart allows both ventricles to relax and be refilled by the contracting atria. After the AV node delay, the ventricles contract and force blood into the aorta (systemic circulation).