The cardiac cycle is the sequence of events that occurs in one complete beat of the heart 🤓 The pumping phase of the cycle, also known as systole, occurs when heart muscle contracts 🔥 The filling phase, which is known as diastole, occurs when heart muscle relaxes. Both ventricles and atria are in diastole at the start of the cardiac cycle. This is when all chambers of your heart relax and are able to receive blood. Open the atrioventricular valves. The phase of atrial systole is immediately following. Atrial systole is when the left and right atriums contract simultaneously and push blood to the left and right ventricles. Next is ventricular Systole. Ventricular systole occurs when both the right and left ventricles contract simultaneously. They pump blood into the pulmonary trunk and the aorta. The atria become relaxed during ventricular syncope and begin to get blood. To stop blood from returning to the atria, the atrioventricular vales close as soon as ventricular systole starts. The semilunar vales are still open in this phase, allowing blood to flow to the aorta or pulmonary trunk. Following this phase,Â the ventricles relax that is ventricular diastole occurs. For blood to be stopped from returning from the pulmonary and aorta, the semilunar valves must close. Once again, the cycle starts again with ventricles and atria in diastole.
There are FOUR CHAMPERS in the heart. In the lower part of the heart, there is the right- and left-ventricles and the right and the left Atria. The normal heartbeat sees the atria contract and the ventricles relax. The ventricles then contract, while the Atria relax. There are VALVES that allow blood to flow between ventricle & atrium. They close so blood does not backwash in the intervals between ventricular contractions. Due to the thick wall that divides right and left ventricles (the VENTRICULAR SEPUM), infants born with “holes in their hearts” will have small gaps. This is because oxygenated and non-oxygenated blood can mix. This is the walls of the had left ventricle are thicker as it has to pump Blood to all tissues, as opposed to the right ventricle that pumps blood only as far as the lungs.
The most important function of the cardiovascular system is to supply oxygen to our bodies. All functions of the cardiovascular system are important, cells require oxygen, brain cells are the most sensitive and begin to die If you are not able to breathe, it can take as long as three minutes. During inhalation, air enters the lungs and oxygen It is then absorbed by the bloodstream via the air sacs. The heart pumps this oxygen-rich blood into the arterial circulation. Oxygen diffuses from the blood through the capillaries into the tissues and organs of the body. The capillaries also allow oxygen to diffuse out of the blood and into cells. carbon dioxide Cell waste products are absorbed by the blood. They then travel to the lungs using the vein circulation. Once this oxygen-poor blood has reached the lungs it diffuses through the sacs into carbon dioxide which is then exhaled. Every breath is a part of this cycle. Modified by Kelly L. from Mudanjiang (China on June 16, 2020).
Based on an article sphweb.bumc.bu.eduThe heart and blood vessels are responsible for transporting oxygen, nutrients and other metabolic byproducts. Through the arterial system, oxygenated and nutrient rich hemoglobin is transported to tissues. The blood vessels branch into smaller and smaller vessels. These blood vessels range from arterioles to capillaries to arteries. The capillaries receive deoxygenated blood, as well as metabolic byproducts via veins. To maintain blood circulation, the heart acts as a pump. Each chamber of the heart can be considered a separate organ. The right atrium and right ventricle of the heart receive blood from the peripheral and then send it to the lung via the pulmonary arterial for oxygenation. After blood has been re-oxygenated by the lungs, it is sent back to the left side via the pulmonary veins. Blood enters the had atrium and flows into the had left ventricle. It is then transferred to the aortic arch where it will be distributed throughout the body. This illustration shows a simplified representation. Many thanks to ChaleeRuffin, Maracay Venezuela for the suggestion.