Erythrocytes or Red Blood Cells (RBCs)
RBCs are the main or most common component of the blood. It delivers oxygen from the lungs to the entire body this blood is known as oxygenated blood and returns with the waste, carbon dioxide, which is known as deoxygenated blood back to the lungs for another cycle.
Mature normal erythrocytes are elliptic, flexible, biconcave disks; which means they are not perfect circles, move/bend to fit through the tiniest blood vessels and are dented on either side of it. They are produced by the bone marrow every 120 days. RBCs contain a protein known as hemoglobin. This hemoglobin (Hb) is what medical scientists use to determine the human genotypes; HbAA, HbAS, HbSS. It is derived from two words, heme; which contains iron that binds to oxygen (in the lungs) and globin; which is made of a series of amino acids (trust me you don't want to know more than this about globin).
This makes hemoglobin a very important and necessary component of the RBCs. Without it, the cells of the body will not be able to have oxygen supply in them and carbon dioxide taken out of them. I guess it is safe for me to finally make it clear that the hemoglobin is responsible for the shape/form of the RBCs. That they can change form also known as genetic mutation. This mutation in hemoglobin gave rise to what is known as hemoglobinopathies. This is generally the term used to describe hereditary blood disorders/diseases......that's right, including the Sickle Cell Disease!
We have arrived!
|A-NORMAL RED BLOOD CELLS|
B-ABNORMAL RED BLOOD CELLS
In sickle cell anemia (SCA), the RBCs hardly last more than 90 days, are majorly sickle or S or C shaped instead of being elliptic; making it abnormal mature erythrocytes. These properties make it highly inflexible and therefore very difficult to pass through tiny blood vessels. This also means oxygen supply to every cell in the body is usually limited. And this can cause anemia, jaundice, fatigue, shortness of breath, exhaustion, pain crisis, and even damages to internal organs.
Yes, SCA is that horrible and scary!
Just A Note: There is a type of hemoglobin produced in babies by the spleen known as fetal hemoglobin (HbF) this is the main oxygen carrier in human fetuses from when they are in the uterus till about 6 months after delivery. This HbF differs from the mature Hb such that it has greater affinity or binding abilities to oxygen. The production starts sometime between the end of the first trimester and the beginning of the second trimester (3-4 months) and is greatly, greatly reduced after 6 months of age.