The contraction and relaxation of the heart is a complex process that brings about the proper functioning of the heart. As the heart is responsible for pumping blood to all parts of the body, it is vital that the contraction and relaxation occur in a synchronized manner. In this article, we`ll explore what happens when the heart contracts and relaxes.
What is the Contraction of the Heart?
The contraction of the heart is called systole. During systole, the ventricles of the heart, which are the lower chambers, contract. This contraction pumps blood out of the heart and into the arteries. The atria, which are the upper chambers, also contract, but this is to a lesser extent. The contraction of the heart is a result of an electrical signal, which is generated by a group of specialized cells called the sinoatrial node (SA node). This signal travels through the heart, causing the chambers to contract.
What Happens During Contraction?
During contraction, the heart muscle fibers become shorter and thicker. This creates pressure that pushes blood out of the heart and into the arteries. The blood in the left ventricle is pumped out through the aortic valve into the aorta, which carries it to the rest of the body. The blood in the right ventricle is pumped out through the pulmonary valve into the pulmonary artery, which carries it to the lungs.
What is the Relaxation of the Heart?
The relaxation of the heart is called diastole. During diastole, the heart muscles relax, and the ventricles fill with blood. The atria also relax and fill with blood. The relaxation of the heart is also a result of an electrical signal, which is generated by a group of specialized cells called the atrioventricular node (AV node). This signal travels through the heart, causing the chambers to relax.
What Happens During Relaxation?
During relaxation, the heart muscle fibers become longer and thinner. This creates a vacuum that allows blood to flow into the heart. The blood in the left atrium flows through the mitral valve into the left ventricle, while the blood in the right atrium flows through the tricuspid valve into the right ventricle.
Conclusion
The contraction and relaxation of the heart work together to ensure that blood is pumped efficiently to the rest of the body. Any disruption in this process can lead to heart disease or heart failure. By understanding how the heart contracts and relaxes, we can better appreciate its importance and take steps to maintain its proper function.