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ERYTHROCYTES (RED BLOOD CELLS). Erythrocytes or commonly known as red blood cells are the most abundant cells found in blood red cells make up 99% of the total blood cells.
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ERYTHROCYTES (RED BLOOD CELLS) Erythrocytes or commonly known as red blood cells are the most abundant cells found in blood red cells make up 99% of the total blood cells. The total volume of blood occupied by the cells is known as Hematocrit; therefore we can also say that Hematocrit is the volume of blood occupied by red blood cells
Mature RBCs are biconcave discs. Mean diameter is 7.8 micrometers. They do not have nucleus, mitochondria and other cell organelles, they only have cytoplasm and Cell membrane and cytoplasmic enzymes for metabolic functions. Although they do not have nucleus, mitochondria and other cell organelles but they are eukaryotes because in early stages red blood cells do have nucleus and organelles but in differentiation stages they lose their nucleus to capacitate more hemoglobin. NORMAL CONCENTRATION OF ERYTHROCYTES IN BLOOD per cubic millimeter In adult male=5,200,000 In adult female=4,700,000 Life span of RBCs=120 days, after 120 days they are ruptured in spleen and the hemoglobin is released.
ERYTHROPOIESIS (Genesis of Red blood cells) • All type of blood cells is formed in the bone marrow by Pluripotential Hematopoietic Stem Cells. These cells are known as Pluripotential because different types of cells are derived from these single types of cells.
Erythropoiesis is the process by which red blood cells are formed.
Sites of Erythropoiesis are: • In the early trimester of fetal life= yolk sac • In middle trimester of fetal life= liver and spleen • In last trimester of fetal life and after birth= bone marrow
Genesis of RBCs • Erythropoiesis begins when non committed stem cells become committed to form different type of blood cells.
DIFFERENT STAGES OF ERYTHROPOIESIS Pluripotential hematopoietic stem cells