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Human Circulatory System

The circulatory system is one of the most important systems in the body. A healthy cardiovascular system needs a proper diet, exercise regimen and routine body analysis.
Marlene Alphonse Jun 18, 2019
The human circulatory system or the cardiovascular system circulates blood and other essential nutrients throughout the body with the help of blood vessels. It is also an organ system whose main function is to transport lymph, hormones, gases and dispel wastes.
The main organ of the circulatory system is the human heart. The cardiovascular system forms a loop in the entire body, starting and finishing at the heart. The blood, blood vessels and the heart comprise the circulatory system in humans.
In the following paragraphs let's take a look at the organs of the circulatory system, along with some of the fascinating facts, about this vital body system. You should be aware of the functions of the circulatory system, to understand its working.

Organs of the Circulatory System

There are 3 basic organs of the circulatory system. They are; the heart which functions as a pump to distribute blood and lymph throughout the body, the blood vessels which transport blood to all the organs of the body and finally the most important component, the blood, which is a medium for transportation and supports the basic functioning of the body. 

The Heart

One of the most crucial organs of the body is the heart. To avoid any injury or trauma, the heart is encompassed with a protective sac called the pericardium. The main function of the heart is transportation of purified blood to various part of the body.
The heart is situated in the left side of the body in the chest cavity and has four chambers - the left auricle, the right auricle, the left ventricle and the right ventricle. Each of these chambers perform independent functions. The heart pumps oxygenated blood to all the organs of the body and sends back de-oxygenated blood back to the lungs.
The right side of the heart circulates used blood from the body to the lungs for reoxygenation, whereas the left half transports replenished blood back to the body. The heart is the only organ in the body that continues working without any rest.
Beating at the rate of 70 to 72 beats every minute, the heart pumps approximately 10 liters of blood throughout the entire body. Without the heart, the human body will simply perish, so it's necessary to lead a healthy lifestyle. 

Blood and Blood Vessels

The blood is made up of a protein called hemoglobin, which responsible for the blood's deep red color. The main components of the blood are red blood cells (erythrocytes) or RBCs, white blood cells (leukocytes) or WBCs and plasma.
The blood is distributed throughout the body with the help of blood vessels. The network of blood vessels consist of arteries, capillaries and veins. Though these are not exactly organs, they play a vital role in the healthy functioning of the body. 
There are billions of blood vessels that are intertwined with each other in an endless network. These blood vessels carry the impure blood from the heart to the lungs and the purified blood back to the heart to be transported to various organs of the body.

The Lungs

Though not actually a part of the cardiovascular system, the lungs have a significant role to play in the process of circulation. The main function of the two lungs that are located in the ribcage, is respiration. The rise and fall of the chest cavity is an evidence of the lungs carrying out their work.
The lungs breathe in oxygen from the atmosphere, which is transported to the heart through the blood vessels. The impure blood is brought back to the lungs which is oxygenated and the impurities are released into the air.

Facts about the Human Circulatory System

It is quite interesting to note that blood travels to every nook and corner of the body, distributing essential nutrients to each cell. This is possible due to the complex network of the cardiovascular system.
  • The human heart is made up of muscles and has three parts - visceral layer (outermost layer), myocardium (middle layer) and the endocardium (innermost layer). The weight of the heart is also different in males and females. In an adult male the heart weighs approximately 300-350 gm. On the other heart, for a female the weight of the heart 250-300 gm.
  • An adult woman has approximately 5 liters of blood and a man has approximately 6.5 liters. Arteries, veins and capillaries help in the transportation of blood. The capillaries are narrow blood vessels that the blood cells must travel in a single file to flow freely.
  • The plasma (yellow colored liquid) which is a component of blood is made up of 93 percent water. The remaining 7 percent of it is plasma proteins.
  • The adult body consists of more than 60,000 miles of blood vessels. If they are strung together, then they could encircle the globe two and half times.
  • A single drop of blood contains about 5 million red blood cells and 12,000 white blood cells. The life span of the blood cells is 4 months, after which they are replenished in the bone marrow.
  • Every second approximately 10 million blood cells die and the same quantity is produced at the same time.
  • The heart beats 30 million times in 365 days. 4000 gallons of blood is pumped by the heart per day. Even after the heart is taken out of the body, it continues beating.
  • When you hear your heart beating, which is indicated as a lub dup, it is the sound of the heart valves opening and closing as the blood is being pushed through the chambers.
  • If you want to know the size of your heart, clench your fist. This is the size of your heart. Imagine the numerous functions performed by an organ, the size of your clenched fist.
  • The aorta is the largest blood vessel in the body. This artery performs the function of transporting blood from the heart to the entire body.
  • Another delicious and interesting fact (especially for chocoholics like me) about the circulatory system is that chocolates are good and improve the health of your cardiovascular system. Since chocolates are rich in antioxidants, they help in lowering blood pressure and reduce the mortality rate due to cardiovascular disorders.
The human circulatory system is one of the most fascinating systems in the human body that carries out various essential functions, without any rest, for the sustenance of life. So it is important to keep this system in good health and avoid unnecessary practices lest it may put a halt to the functioning of this vital system.