All the organisms present on earth survive on food, water, minerals, and oxygen. Life is impossible if all these factors do not come into play. These are the basic requirements of any organism for its survival. However, these components must be transported to all parts of the body that require them. The body needs them for energy and growth. Additionally, even the waste materials need to be transported to excrete them out of the body.
Out of all the parts in the body, the human heart is one of the most crucial parts without which it is impossible to function. The heart is the pumping organ of the body. It pumps blood all the time. It helps in transporting blood to all the parts of the body. The heart pumps blood through the set of connections between veins and arteries. Today, here, we are going to discuss the cardiac cycle and Ventricular Filling Stage in detail.
Explain the Cardiac Cycle
In simple terms, the cardiac cycle can be described as the process of alternating relaxation and contraction of ventricles and atria to pump blood across the body. The process starts with the beginning of a heartbeat and ends at the beginning of another one. It mainly includes systole, intervening pause, and diastole. The heart rate determines the occurrence of the entire cardiac cycle indicated naturally as beats every minute. The entire cardiac cycle begins at the 4th gestational week. This is the time when the heart first starts to beat in the foetus.
In normal conditions, a human heart beats 72 times in a minute, which means that in 60 seconds, 72 cardiac cycles take place. This cycle involves both relaxation and contraction of ventricles and atria. One cycle only lasts for around 0.8 seconds.
What are Blood Vessels?
Blood Vessels are described as tube-like structures wherein the blood flows throughout the body. It is a group of connected vessels which allow the blood to flow through your body, known as blood vessels. The two types of blood vessels present in a human body are:
Arteries: They help in carrying blood that is rich in oxygen from the heart to all parts of the body. The blood flows at a high speed and pressure through the arteries. This results in thick elastic walls for the arteries.
Veins: These types of blood vessels help in carrying blood that is carbon dioxide-rich from the organs of the body. They take it back to the heart. The veins have thin walls. They have valves that direct the blood towards the heart. The arteries are divided into smaller blood vessels. They are divided into further thinner tubes known as blood capillaries.
What is Rapid Ventricular Filling?
The Ventricular Filling Stage is one of the major phases of a cardiac cycle which mainly includes three further stages. These are as follows –
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Early ventricular diastole
At the time of the early ventricular diastole, the pressure in the 2 ventricles starts dropping from the highest. As the pressure in the left ventricle starts to fall compared to the pressure in the left atrium, it leads to the opening of the mitral valve because of the negative pressure between both chambers. It allows the blood in the atrium to flow in the ventricle. Similarly, the same process is repeated in the right ventricle and right atrium.
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Late ventricular diastole
During the late ventricular diastole, both the atrial chambers tend to contract, which increases the blood pressure in the atria and forces more blood flow in ventricles. This process is referred to as the atrial kick. During the cardiac cycle, the atrial kick does not promote an extensive supply of flow; hence around 80% of the filled blood volume travels to the ventricles at the time of the active suction period.
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Atrial diastole
When the cardiac cycle starts, the entire heart, which includes the four chambers, two atria, and two ventricles, approaches dilation or diastole and relaxation in sync. The atria are filled with blood volumes which later return to the right atrium then to the left atrium. In short, during the time when ventricles are in contracting and systole, the atria gets relaxed and fills the returning blood.
During the last diastole, the ventricles are completely dilated, the atria contracts while pumping blood to the ventricles. This coordination of all four chambers of the heart ensures that the blood is pumped rightly and circulated throughout the body without any failure. In the entire cardiac cycle, blood vessels play a significant role.
What Happens During Ventricular Filling?
During the ventricular filling stage, both the ventricles are filled with the blood in both stages including atrial systole and diastole. In diastole, ventricles and atria, both are relaxed before it flows directly into ventricles. They are filled with the blood at a describing rate till the time the pressure is same as that of veins.
Conclusion
With this, we come to the end of the topic Ventricular Filling Stage in Biology. The heart is the pumping organ of the body. It pumps blood all the time. It helps in transporting blood to all the parts of the body. The heart pumps blood through the set of connections between veins and arteries. If the human heart spots its functioning, it can lead to sudden cardiac failure and untimely death.
The cardiac cycle is the process that starts with a heartbeat production to the commencement of the upcoming beat. It mainly includes systole, intervening pause, and diastole. We hope the Ventricular Filling Stage explanation is clear to everyone.