Sinoatrial node
No, the sinoatrial (SA) node initiates contraction of the atria, which subsequently causes stimulation of the AV node, which then initiates contraction of the ventricles via the Purkinje fibers.
the purkinje fibers um no!!! wrong answer!!
the sinoatrial (SA) node
At the AV node, the impulse is delayed for about 0.1s, allowing the atria to respond and complete their contraction before the ventricles contract.
There is only one SA(sinoatrial) node. It is located by the right atrium of the heart. it initiates the nerve impulse which travels through both atria to initiate atrial contraction. Then the impulse travels to the AV(atrial ventricular) node. the nerve impulse travels through the intraventricular septum to the apex of the heart, where it initiates the contraction of the ventricles(starting from the apex and squeezing the blood up and out of the arteries).
the atriventriculart node causes both atria to contract
The sinoatrial node (SAN) is located within the walls of the right atrium. It is from here the initial stimulus for contraction of the atria originates.
SA node sends an impulse for the atria to contract. AV node is then activated which contracts the ventricles.
It simulates the node, which then sends impulses to the AV node, which disperses these impulses through the cardiac muscle to cause a cardiac cycle (rhythmic beating and relaxing of atria and ventricles)
The AV node typically delays the signal from the SA node by about 0.1 to 0.2 seconds. This delay allows time for the atria to contract and fill the ventricles with blood before the signal is transmitted to the ventricles.
The atria contract during the cardiac cycle's atrial systole phase, which occurs just before the ventricles contract. This contraction helps push blood from the atria into the ventricles, completing the filling of the ventricles before they contract during ventricular systole. Atrial contraction is facilitated by electrical signals from the sinoatrial (SA) node, ensuring synchronized heart function.
The Cardiac Control Centre (CCC) is located in the brain, and controls the impulses created in the heart by the Synal Atrial node (SA node) as well as the impulses in the Atrioventricular node (AV node). The 'CCC' therefore controls systole in the atria and ventricles, and consequently heart rate is heightened or reduced based on the commands the Cardiac Control Centre gives out.