Erythropoiesis Flashcards
What is haematopoisis ?
The process in which immature precursor cells develop into mature blood cells.
What is the name of the stem cell that gives rise to mature blood cells in the body ?
The stem cell is called pluripotential(pluripotent) stem cell
What is the characteristic of stem cells in bone marrow?
- Reproduce themselves
- Proliferate and differentiate
What is immature cell in bone marrow called?
Blast cell
How blood cells enter blood the bloodstream?
Through sinusoids. A sinusoid is a form of blood channel usually described as a large, irregular capillary, having a discontinuous lining of endothelium, with little or no adventitia; sinusoids are found in theliver, spleen, and bone marrow
How blood cells enter blood the bloodstream?
Though Hi, I am sinusoids. A sinusoid is a form of blood channel usually described as a large, irregular capillary, having a discontinuous lining of endothelium, with little or no adventitia; sinusoids are found in theliver, spleen, and bone marrow
What type of cells can pluripotent stem cells produce? And what is the function of each of the cells?
Pluripotent stem cells produce:
- Myeloid stem cells. Its function is to give rise to rbc, platelet, monocytes, neutrophils, eosinophils, and basophils.
- Lymphoid stem cells. Its function is to give rise to lymphocytes.
What are growth factors that regulate differentiation and proliferation in hemopoietic?
Erythropoietin(Epo)-RBCs
Thrombopoietin-platelets
Colony-stimulating factors(CSFs) and interleukins-WBCs
What are 2 types of bone marrow and explain its characteristic?
Two types:
- Red bone marrow, colour due to blood and blood forming cells.
- Yellow bone marrow, colour due to great number of adipose tissue
- In newborn, all bone marrow is red*
What is the function of red bone marrow?
- Production of blood cells
- Destruction of worn-out RBCs
- Storage(in macrophages) of iron derived from breakdown of haemoglobin
What is the structure of red bone marrow?
● Stroma.It forms the supportive tissue of red bone marrow and creates a microenvironment conducive to hematopoiesis.
●Meshwork of reticular cells in delicate web of reticular fiber.
●Collagen type 1 and 2.These are the primary types of collagen found in the reticular fibers. Type I is stronger and provides mechanical strength, while Type III is more delicate and forms fine networks.
● Fibronectin, Laminin, and Hemonectin: These are extracellular matrix glycoproteins that bind to cell receptors and help in the adhesion of cells to the stroma.
●Hematopoietic cords.These include the precursor cells for all the blood cell types, such as erythrocytes (red blood cells), leukocytes (white blood cells), and platelets.
●Sinusoidal Capillaries. These are wide, thin-walled capillaries that allow newly formed blood cells to enter the bloodstream. They are reinforced by an external discontinuous layer of reticular cells and a loose net of reticular fibers, which support the vessel walls while maintaining flexibility.
In erythropoiesis, what is the basic of maturation?
The basic process of maturation is synthesis of haemoglobin and formation of enucleated, biconcave erythrocytes
In erythropoiesis, what is the basic of maturation?
The basic process of maturation is synthesis of haemoglobin and formation of enucleated, biconcave erythrocytes
During the maturation of red blood cells in erythropoiesis , what changes that occur in the rbc?
Changes during maturation:
▪︎ Decrease in cell volume
▪︎ Nucleoli diminish in size until invisible in scope.
▪︎ Nuclear diameter decrease and chromatic become denser until nucleus have a pyknotic appearance and finally extruded.
▪︎ Decrease number of polyribosomes (basophilia decrease) with an increase in haemoglobin (acidophilic).
▪︎ Cell organelles gradually disappear.
During the maturation of red blood cells in erythropoiesis , what changes that occur in the rbc?
Changes during maturation:
▪︎ Decrease in cell volume
▪︎ Nucleoli diminish in size until invisible in scope.
▪︎ Nuclear diameter decrease and chromatic become denser until nucleus have a pyknotic appearance and finally extruded.
▪︎ Decrease number of polyribosomes (basophilia decrease) with an increase in haemoglobin (acidophilic).
▪︎ Cell organelles gradually disappear.
