Table of Contents
What part of the heart controls electrical impulses?
SA node
The heart’s electrical system SA node (sinoatrial node) – known as the heart’s natural pacemaker. The impulse starts in a small bundle of specialized cells located in the right atrium, called the SA node. The electrical activity spreads through the walls of the atria and causes them to contract.
What is the function of the SA node?
The SA (sinoatrial) node generates an electrical signal that causes the upper heart chambers (atria) to contract. The signal then passes through the AV (atrioventricular) node to the lower heart chambers (ventricles), causing them to contract, or pump. The SA node is considered the pacemaker of the heart.
Are there electrical impulses in the heart?
The heart generates its own electrical signal (also called an electrical impulse), which can be recorded by placing electrodes on the chest. This is called an electrocardiogram (ECG, or EKG). The cardiac electrical signal controls the heartbeat in two ways.
How do electrical impulses work in the heart?
When the SA node sends an electrical impulse, it triggers the following process: The electrical signal travels from your SA node through muscle cells in your right and left atria. The signal triggers the muscle cells that make your atria contract. The atria contract, pumping blood into your left and right ventricles.
What is SA node class 10?
The sinoatrial node or SA node is called the natural pacemaker of the heart. The impulse initiates in a small bundle of special cells found in the right atrium, it is known as the SA node.
What activates the SA node?
The parasympathetic nerves supplying the SA node (in particular the Vagus nerves) originate in the brain. These nerves release a neurotransmitter called acetylcholine (ACh). ACh binds to a receptor called an M2 muscarinic receptor, located on the SA node membrane.
How are electrical impulses produced?
Neurons conduct electrical impulses by using the Action Potential. This phenomenon is generated through the flow of positively charged ions across the neuronal membrane.
How are electrical impulses generated in the heart?
An electrical stimulus is generated by the sinus node (also called the sinoatrial node, or SA node). This is a small mass of specialized tissue located in the right upper chamber (atria) of the heart. The sinus node generates an electrical stimulus regularly, 60 to 100 times per minute under normal conditions.