The circulatory system is an apparatus that exists both in vertebrates and in most invertebrates, although its function and structure varies. It is defined as an internal transport system through which nutrients, oxygen, hormones, carbon dioxide and other substances move throughout the body. In the case of humans, the circulatory system is made up of blood, a network of ducts (veins, capillaries, and arteries), and the heart.
The heart is the strongest muscle in the body
The human body has more than 650 muscles, which make up 50% of body weight. Well, the strongest of all is the heart. It never stops working and is constantly under great pressure. To this we must add that, despite its small size, it is capable of pumping blood at a speed of two kilometers per hour to reach all parts of the body .
More than 7,000 liters of blood daily
Incredible as it may sound, the heart pumps 70 milliliters of blood with each beat. Therefore, taking into account that it beats about 80 times per minute , the result is five liters of blood in a single minute. This equates to 7,000 liters of blood.
The first investigations date from the 16th century BC
The circulatory system has been the object of study by numerous civilizations throughout history . It is believed that the Egyptians were the first to do so, convinced that the heart was the most important organ in the body. They thought it was the source of memories, emotions, and wisdom.
The pipeline network measures 80,000 kilometers
One of the great curiosities about the circulatory system is that if we took all the capillaries, veins and arteries and put them in a straight line, we would obtain a thread of more than 80,000 kilometers. To give us an idea of what this means, the diameter of planet Earth is 40,000 kilometers .
The broken heart exists
When someone breaks up with their partner, it is said that they are heartbroken. Although it may seem like a simple metaphor, the truth is that a very strong emotion such as a romantic breakup can cause damage to the heart, even leading to cardiac arrest .
As you can see, the circulatory system is a very interesting device.
