What is the circulatory system?
We explain what the circulatory system is and its main functions. In addition, the parts that compose it and their possible diseases.
The circulatory system allows the transfer of different nutrients.
The circulatory system or circulatory system is a complex internal transport mechanism that possesses to varying degrees the body of living beings, and allows the transfer of various nutrients, regulatory substances, chemical defenses and other fundamental substances throughout the body, as well as the collection of toxins, metabolic by-products and other waste materials for disposal.
This type of system exists in both vertebrate and invertebrate animals, although not in the same way. In the case of the former, it transports blood, a red fluid rich in iron that allows, among other things, the transfer of the oxygen necessary to obtain energy. In the case of the latter, haemolymph or other similar substances are transported; in the case of plants, sap.
The human body’s circulatory system includes a vast network of blood vessels known as capillaries, which are connected to a larger network of veins and arteries. At the center of it all, a muscle pump known as a heart.
When we cut or injure ourselves, the blood sprouts because some (usually minor) stretch of the network is violated. Fortunately, the cells responsible for repairing tissue and stopping minor bleeding are also carried in the blood.
Function of the circulatory system
The circulatory system displaces chemicals such as white blood cells or hormones.
As has been said, the function of the circulatory system is key: keeping the blood moving to oxygenate the body and preserve the life of the tissues.
If any tissue were isolated from this vast blood network, any limb or organ, its cells would suffer from a lack of oxygen and die. This is called ischemia.
In the same way, this apparatus has the mission of communicating the whole body, allowing the displacement of chemical substances of diverse nature, such as hormones (to regulate the activity of the body), white blood cells (and other defensive cells), or the necessary nutrients to produce new cells and tissues (carbohydrates, proteins and lipids).
Even the medicines we take or the injections we receive use this transportation system to get where they’re needed.
Finally, circulating blood also passes through certain filters, such as the liver, where it is stripped of toxins, pollutants and substances produced by metabolism. The circulatory system is both a nutrition channel and a waste collection channel.
Parts of the circulatory system
The heart is a hollow muscular organ that weighs about 300 grams.
The circulatory system consists essentially of:
- Capillary vessels. Small branches of the blood network that reach to the most hidden corners of the body. No tissue in the body is left out of the blood flow. Some capillaries can be thinner than a human hair.
- Arteries. One of the two major types of blood vessels, it is characterized by carrying freshly oxygenated blood from the lungs to the heart and from there to the rest of the body. They contain the reddest blood (due to a pigment called hemoglobin). An injury to an artery can be serious, since the volume of blood transported through them is very large, and does not always give time to repair the wound to prevent bleeding.
- Veins. Contrary to the arteries, these major conduits contain unoxygenated blood, that is, blood that begins the journey back to the heart and then to the lungs, to resume the cycle. Like arteries, they are bulky ducts and a cut or blockage in the veins is usually lethal.
- Sweetheart. The pump that keeps the blood moving constantly is a hollow muscular organ that weighs about 300 grams and contains four cavities: two atria and two ventricles. This construction prevents venous and arterial blood from mixing, as each is propelled to a different destination. The human heart pumps about five liters of blood per minute, which means that in about 70 years of life it pumps about 2600 million times, with a tiny rest between beats of just 0.4 seconds.
Diseases of the circulatory system
Arteriosclerosis is the accumulation of fat in the walls of the arteries.
The circulatory system can suffer from diseases such as:
- Arteriosclerosis. An ailment that consists of the accumulation of fat plaques and other substances in the walls of the arteries, solidifying and decreasing the flow of blood, which slows the circulation and requires greater cardiac effort.
- Hypertension. Due to many possible causes, it consists of an excess of force in the heartbeat, which sends blood very intensely through the arteries, eventually breaking a capillary and produce a stroke, or exhaust the heart and lead to a heart attack.
- Ischemia. They usually affect the heart or brain, but also other organs or members of the body. They occur when something obstructs the flow of blood, causing some part of the body to not receive enough blood and begin to die.