The Circulatory System by Doctor_dr

By Microbiology Doctor-dr

The Circulatory System 

The heart was supposed to be the seat of all emotions in ancient times. People used to believe that the heart was in charge of life's songs and that it dictated whether or not a person fell in love. The heart is still a popular symbol of love today. However, experts today recognize the heart as one of the body's most powerful organs. Your circulatory system is made up of your heart and a branching network of major and tiny blood arteries. It's also known as your circulatory system. Plate Six shows a thorough representation of the circulatory system. All of your cells receive life-sustaining nourishment through your circulatory system. At the same time, it collects and disposes of garbage.

The Structure of the Heart

Your heart is the muscle pump located in the center of your upper chest cavity, between your lungs. It's around the same size as your clinched fist. It sends blood through the blood vessels of your body by beating constantly, about 60 to 80 times every minute when you are at rest.

The heart is a double pump. The right side of the heart receives oxygen-poor blood from the body and pumps it to your lungs. The left side of the heart receives oxygen-rich blood from the lungs and pumps it to your body.

An inner wall of muscles separates your heart into a right and a left side. Normally, this wall has no openings.

Figure 12-1 Atria pump blood into the ventricles (left). Ventricles pump blood to the lungs and the body (right).

Your heart is further separated into two chambers, one on top of the other, on each side. A one-way valve separates the two compartments. An atrium (AY tree um) is the upper chamber of the heart. A ventricle [VEN trih kul] is the lowest chamber of the heart. The atrium, located on the right side of the heart, receives oxygen-depleted blood from the body. The blood is pumped via the valve into the right ventricle, which is the lower chamber. The right ventricle is responsible for pumping oxygen-depleted blood to the lungs.

The left side of the heart is divided into an atrium on top and a ventricle underneath, same like the right side. The left atrium is somewhat bigger than the right. Its duty is to take oxygen-rich blood from the lungs and deliver it to the rest of the body. The blood is subsequently sent to the left ventricle through the valve. The left ventricle's wall is thicker and more muscular than the right ventricle's. Because it pumps oxygen-rich blood to the body, the left ventricle is bigger than the right ventricle.

The flow of blood through the chambers of the heart is shown in Figure 12-1. Both atria and ventricles pump at the same time, as you can see in the diagram. The alternating closure of the valves in the atria and ventricles produces the sound of a heartbeat.

The Circulatory Vessels

The circulatory system in your body is a closed system. This implies that all of the blood stays trapped in the system until a section of it is wounded or opened. Throughout your body, your blood takes the same courses again and over.

Blood vessels come in five different types. The arteries, veins, arterioles, capillaries, and venules are the arteries, veins, arterioles, capillaries, and venules. Arteries and veins are the major blood vessels. Blood channels that convey blood away from the heart are known as arteries. The walls of arteries are thick and muscular. The major artery is the acrta [ay AWR tuh]. The aorta transports oxygen-rich blood from the left ventricle to the rest of the body through a branching system of smaller arteries. Blood vessels that deliver blood to the heart are known as veins. The walls of veins are thinner than those of arteries. Veins feature valves that prevent blood from backing up, as seen in Figure 12-2.

Figure 12-2 Blood flowing through a vein towards the heart opens the valve (left). When blood backs up in the vein, the valve closes (right).

Your body's circulatory system is a closed system. This means that unless a piece of the system is damaged or opened, all of the blood is contained within. Your blood follows the same paths throughout your body again and over.

There are five main kinds of blood vessels. Atherosclerosis affects the arteries, veins, arterioles, capillaries, and venules. The principal blood vessels are arteries and veins. Arteries are blood vessels that carry blood away from the heart. Arteries have robust and muscular walls. The acrta [ay AWR tuh] is the main artery. Through a branching system of smaller arteries, the aorta delivers oxygen-rich blood from the left ventricle to the rest of the body. Veins are blood channels that carry blood to the heart. Vein walls are much thinner than artery walls. As seen in Figure 12-1, veins include valves that prevent blood from backing up.

Pulmonary Circulation

Blood goes from your heart via one of two circulatory system subsystems. Blood flows via one of the subsystems and into the lungs, where it releases carbon dioxide and takes in the oxygen your cells need to produce energy. Blood, on the other hand, circulates around your body, providing oxygen to the cells and collecting waste products such as carbon dioxide.

Pulmonary circulation refers to the flow of blood from the heart to the lungs. Blood from the right ventricle goes via the pulmonary arteries to a network of blood vessels in your lungs through this channel. As they pass through the small air chambers of your lungs, the veins get thinner and thinner. Carbon dioxide may flow out of the vessels and oxygen can enter in because to the thin walls of the vessels and air saes. As they approach the heart, the vessels coming from the lungs broaden. The left atrium receives blood from the lungs. The blood in the arteries of the pulmonary circulation is oxygen-depleted. The blood in the pulmonary veins is high in oxygen. It's important to remember that arteries transport blood out from the heart and veins bring blood back.

Systemic Circulation

The systemic circulation is the subsystem that transports oxygen-rich blood to all regions of the body save the lungs. Arteries transport oxygen-rich blood, whereas veins carry oxygen-poor blood in the systemic circulation. Within this system, three of the most major blood channels transport blood to and from the heart, kidneys, and liver walls.

Circulation in the Coronary Artery Because the heart's muscles are always working, they need a steady supply of oxygen and nourishment. The blood that flows through the chambers of your heart does not feed the heart muscle, contrary to popular belief. Coronary arteries, on the other hand, are the blood channels that transport nutrients and oxygen to the heart muscle. These are the first arteries that emerge from the aorta. They split into several smaller branches, each of which ends in a capillary. Blood returns to the right atirum of the heart through a system of veins after passing through the capillaries.

Circulation in the Renal System Because the kidneys assist in the removal of wastes from the blood, blood circulation to and from the kidneys is critical. The kidneys get one-fifth of the blood that exits the heart. Renal arteries carry blood from the aorta to the kidneys. The renal veins drain into a huge, central vein that returns blood to the heart.

Circulation via the portal Before this blood can be transferred to the heart for recirculation, any potentially harmful substances must be eliminated. This blood is sent to the liver, where it is cleansed. The portal vein is the blood channel that transports blood to the liver for cleaning. Blood from arteries nourishes the liver's tissues. Before returning blood to the heart, the liver eliminates harmful chemicals. The blood then travels via the veins back to the heart.

Lesson Review

Blood transports nutrients and other substances to and from the body's cells. The system is powered by the heart. Other important organs of the body obtain appropriate blood supply when the heart pumps properly.