The red blood cells are blood cells also known as erythrocytes or red blood cells.
They play an important role in tissue oxygenation and are also responsible for the red color of the blood.
Characteristics of red blood cells
The red blood cells are rounded cells , shaped like a biconcave disc , which are about 7.5 µm in diameter and 2.6 µm thick in the peripheral region and about 0.8 µm in the central region.
The shape of the red blood cells increases the contact surface, ensuring a more efficient gas exchange.
In addition, red blood cells are flexible, which facilitates transport.
Red blood cells also stand out for the absence of nuclei and, therefore, of genetic material.
Due to this characteristic, red blood cells are cells that live for a short period of time and are unable to divide.
The red color of the red blood cells is the result of a red pigment called hemoglobin .
Hemoglobin is a protein made up of four subunits that have a portion of protein attached to a group of heme that contains iron.
It is this protein that is responsible for ensuring the transport of oxygen throughout the body.
Red blood cells are produced (erythropoiesis) in the bone marrow and, after an average period of 120 days, their destruction occurs, which is done in the liver and spleen.
At these sites, hemoglobin molecules break down and amino acids and iron are available, which can be used to produce new red blood cells.
Importance and function of red blood cells :
Red blood cells are important for the transport of oxygen obtained through the respiratory system to the body’s cells.
Another function of the red blood cells is to transport part of the carbon dioxide produced by the cells so that it can be eliminated.
It should be noted that much of the carbon dioxide that is produced in the tissues is transported by the blood plasma.
When it reaches the lungs, more precisely the lung alveoli, hemoglobin binds to oxygen molecules, forming oxyhemoglobin.
In tissues, hemoglobin combines with carbon dioxide to form carbohemoglobin.
Anemia is the name given to diseases that are characterized by low levels of hemoglobin in the blood.
This problem has several causes, such as a low iron diet or a low red blood cell production, excessive destruction of these cells and severe bleeding.
In anemia, oxygen transport is affected and, consequently, cells perform the process of cellular respiration in smaller amounts.
Without intense cellular respiration, less energy is produced and the individual feels greater weakness and fatigue.
Also noteworthy is the existence of sickle cell anemia , a hereditary disease characterized by the deformation of red blood cells, which in this case is shaped like a sickle.
This change in red blood cells makes them less flexible and more fragile than normal red blood cells, which causes their rapid destruction.