Our heart is roughly the size of a clenched fist and is located in the middle of your chest between tow lungs, tilted more to the left. This small, fist-sized organ is one of the most critical organs of the body, the centre of the circulatory system and responsible for pumping blood and oxygen throughout the body. It also removes carbon dioxide and waste products. With every breath that you take, you bring in fresh oxygen in the body through the lungs, the lungs deliver this oxygen to the blood and then the heart circulates the blood to the lungs and other body organs.
Structure of the Heart
The heart is made of three layers of tissues, namely:
These three layers are further protected by a thin outer lining known as the pericardium.
Circulatory System of the Heart
The heart comprises of four chambers – two upper and two lower chambers, known as the atrium and the ventricles respectively. These chambers are divided by a wall of muscle called the septum. The right atrium is above the right ventricle and the left atrium is on top of the left ventricle. The right chambers including the right atrium and right ventricles are responsible for pumping blood to the lungs and supplying oxygen from the lungs to the left chambers of the heart consisting of the left atrium and left ventricles. From the left chambers, the oxygenated blood is then pumped to the other parts of the body, enabling effective functioning. The cells from the other parts of the body return the blood (devoid of oxygen) to the right chambers of the heart, and then the process begins again. This whole functioning is referred to as the process of circulating blood in the body. The functioning is supported by blood vessels and valves, which collectively is known as the cardiovascular system. An average heart daily pumps five litres of blood in the body.
Blood Vessels of the Heart
The blood vessels play a very critical role in circulating the blood through the body. These blood vessels tend to change their size depending on the amount of blood needed to carry for each part; this process is controlled by hormones. Blood vessels support the circulatory system in the following manner:
Arteries: These blood vessels are responsible for carrying oxygen-rich blood from the heart to the other organs of the body.
Capillaries: These tiny connectors help the smallest arteries connect to the smallest veins and trade water, oxygen, carbon dioxide and nutrients between the blood and surrounding tissues.
Veins: These are responsible for carrying non-oxygenated blood back to the heart for processing.
Valves of the Heart
The heart comprises of four valves that help to keep the blood flow in the right direction. These four valves are:
- Aortic Valve located on the left side of the heart
- Mitral Valve located on the left side of the heart
- Pulmonary Valve located on the right side of the heart
- Tricuspid valve located on the right side of the heart
Electrical System of the Heart
The electrical system of the heart is controlled by its natural pacemaker called the sino-atrial node – located in the right atrium. This pacemaker sends signals to the heart muscle guiding it to contract and relax, in order to pump blood in the body continuously. The electrical signal from the pacemaker is sent to the atria making them contract and pump blood into the ventricles via the valves. When the atria meet the ventricles, electrical signals are passed throughout the heart muscle that enables the ventricles to contract and pump blood via the pulmonary and aortic valves to the main arteries. These electric signals to the heart muscle are carried by electrical pathways called the conducting system. Once the cycle is completed, the natural pacemaker of the heart sends out another electrical signal initiating another round.
Blood Pressure of the Heart
The pressure of blood in the arteries lays the foundation of how effectively blood is delivered to all other organs of the body. The pressure of the blood defines the flow of blood to the blood vessels which in turn is also impacted by three basic parameters:
- The pumping of blood in the heart
- The size and flexibility of the blood vessels
- The thickness of the blood
Altogether, a single heartbeat is the entire composition of the contraction and relaxation of the heart, pumping blood. On an average, a normal heart beats about 60-100 times per minute which fluctuates depending on the situation, such as during exercise or physical workout. To ensure proper blood supply, the entire functioning of the heart has to happen in the right order and method. Any discrepancies cause a disorder and can result in various problems. Share0