Red Blood Cells:
Red Blood Cells(RBC) or erythrocytes are the cells responsible for carrying hemoglobin. Their count determines the viscosity of blood. Their normal count is between 5-6 million cells per cu.mm of blood. Erythropoiesis is the production of RBCs. Alteration in number or shape may result in anemia.RBC are also known as erythrocytes because of their red colour.
Production:
RBCs are are produced in the red bone marrow of flat bones like skull, ribs, sternum. The production of RBCs is called as erythropoesis. It takes place for 6-7 days.
Factors determining erythropoiesis:
Hypoxia - The need for oxygen by the tissues is the major drive for erythropoiesis.
Erythropoeitin - Erythropoietin is an important hormone produced by the kidneys in response to hypoxia. Hypoxia refers to decreased oxygen levels in blood.
Castle`s intrinsic factor - Castle`s intrinsic factor is a glycoprotein produced by the stomach. It is required for the absorption of vitamin B12 which is required for erythropoiesis.
Other minerals - Erythropoiesis requires minerals like iron, cobalt, manganese.
Life Span:
RBC lives for an average of 120 days.
Destruction:
RBCs are destroyed in the spleen. Thus spleen serves as a graveyard for old RBCS.
Function:
RBCs serve as a carrier of hemoglobin. Hence it helps in the transfer of gases across the body. The hemoglobin present in it serves as a buffer to neutralize the pH of plasma.