Blood is a liquid substance that circulates through the body through blood vessels, and is responsible for transporting cells that perform basic functions for life. It has a fundamental role in the transport of oxygen and nutrients, but the blood also collects carbon dioxide and other waste substances, for their subsequent elimination by the organs of excretion.
The volume of blood in a human body depends on sex, age and complexion, but is estimated to be 7% of body weight.
What are the blood’s components?
Blood is a mixture of several components: plasma, white blood cells, red blood cells, and platelets.
Plasma
It is the liquid part of the blood, where the other components are suspended. It constitutes 55% of its volume. Plasma is made up of water, and a mixture of proteins and electrolytes.
The most abundant protein is albumin, which prevents blood from seeping out of the blood vessels so that it does not enter the tissues. It has the ability to bind to certain substances, such as some drugs and hormones, so it also acts as a transport.
Plasma has a higher density than water and is yellowish in color.
Red blood cells
Red blood cells, erythrocytes or red blood cells are the most abundant cells in the blood, representing 40% of its volume. They contain hemoglobin, which is the protein that gives it its characteristic red color, and thanks to which it can collect the oxygen obtained in the lungs and distribute it throughout all the tissues of the body .
Cells use oxygen to generate the energy necessary to perform their functions. This process generates a waste that is carbon dioxide. Red blood cells are also responsible for transporting it, making a reverse journey from the tissues to the lungs.
When the level of red blood cells is deficient, anemia occurs and the blood carries less oxygen than necessary, which causes weakness and fatigue. On the contrary, if it is too high, the blood can acquire a too thick consistency, which makes it more prone to clotting. This would increase the risk of stroke or heart attack.
White blood cells
Also called leukocytes, they have a lower ratio in the blood than red blood cells, roughly one leukocyte for every 600 erythrocytes. Its main function is to protect the body against infection . There are different types of white blood cells.
- Neutrophils. The most numerous, are responsible for destroying bacteria, fungi and debris.
- Lymphocytes They are divided into three classes: T cells, NK cells ( natural killer ) and B cells. They fulfill different defense functions such as detecting viruses and cancer cells, to try to destroy them. They also produce antibodies, which are responsible for neutralizing threatening external elements. .
- Monocytes Its job is to ingest damaged or dead cells. In addition, they collaborate in the defense against infectious microorganisms.
- Eosinophils. They are able to destroy cancer cells and eliminate parasites. They are also related to allergic reactions.
- Basophils . They also participate in allergies.
Platelets
They are the smallest cells and their role is to repair blood vessels and form clots to heal wounds . When bleeding occurs, platelets clump together, forming what is known as a platelet plug, with which they seal the ruptured blood vessel to stop the bleeding.
These are the four components of blood, which can also be classified into four blood groups, A, B, AB and O. Each one is determined by the composition of molecules called antigens.
Blood is, so to speak, the body’s fuel, one of the wonders created by nature. Each drop contains the ingredients necessary to keep the incredible machine that is the human body alive.
