BLD 324 EXAM ACTUAL QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS GRADED A++
Three phases of hematopoesis
Mesoblastic (yolk sac) phase
Hepatic
Medullary (Myeloid phase)
Mesoblastic (Yolk sac) phase
Phase that begins about 19 days after fertilization which includes erythroblast,
mesodermal cells, and hematopoeitic stems cells (HSCs), prodcution of hemaglobin
(Gower 1 and Gower 2), and formation of blood vessels by angioblasts.
Hepatic phase
Phase that begins around 4-5 week of gestation peaking around the 3rd month.
Primarily in the liver. Clusters of developing erythroblasts, granulocytes, and
monocytes. Begin definitive hematopoesis and production of HbF.
Medullary (Myeloid) phase
Phase that begins around 5 months of gestation and marrow becomes the primary site
of hematopoiesis. Myeloid to erythroid ratio is now 3:1. Extramedullary hematopoiesis
subsides. Less HbF, more HbA, HbA2
Hematopoietic tissue in adults
Thymus, lymph nodes, bonemarrow, liver, spleen
Active bone marrow location in adults
,Sternum, pelvis, ribs, vertebrae, skull, proximal ends of long bones.
Red Marrow
Hematopoietically active bone marrow
In all bones until the age of 7, bone marrow slowly is replaced by yellow marrow and is
then restricted to specific sites.
Yellow Marrow
Hematopoietically inactive. Adipocytes (fat cells)
Hematopoietic cords
Extravascular cords of the active red marrow between the spongy bone and trabeculae.
Forms the parenchyma of the bone marrow. Provides a lattice or meshwork (of reticular
cells) to support blood cell development. Productioin of cytokines, ahesive molecules,
steroid secretion (controls volume of bone marrow).
Increased red marrow
can be caused by leukemia and high altitude
Decreased red marrow
can be caused by aplastic anemia
Sinsusoids
Venous sinus (specialized vein) which provides venous drainage to the marrow. Has an
endothelial lining with a discontinuous basement membrane (collagen). Cells may leave
the marrow by enetering the parenchyma and move into the venous sinus to enter the
blood stream via the central vein.
Megakaryocytes
In bone marrow produces platelets
,Hematopoietic microenviornment
Protein carbohydrate matrix, adhesion molecules, cytokines (colony stimulating factors,
inteferons, interluekins, lymphokines
Extramedullary hematopoiesis
hematopoiesis that occurs outside of the bone marrow
Liver function in extramedullary hematopoiesis
Liver is the major site of hepatic phase/stage in which bone marrow is shut down/
inactive and the liver sequesters and removes damaged red blood cells. Often happens
as a result of porphyrias, hemolytic anemias, RBC dysplasia
Spleen function in hematopoiesis
Filters circulating blood
Lymph nodes in hematopoiesis
Site of B cell proliferation (germinal centers) and filtration of microrganisms
Thymus
Site of T cell condtioning
Stem Cell theory
Pluripotential stem cells give rise to all marrow cells.
Daughter cells either give rise to itself, or other daughter cell differentiates and matures.
Hematopoietic stem cells (HSC)
Cells charichterized by CD34 markers, no HLA-DR antigen, no antigens associated wih
more differentiated cells. Not morphologically identifiable.
Progenitor cell
, undifferentiated hematopoietic stem cell with a committed cell line, but not identifiable
morphologically.
Myeloid progenitor markers
CD33 CD38
Lymphoid progenitor markers
CD10 CD38
T- Lymphoid and NK cell progenitor markers
CD7
B-Lymphoid progenitor makers
CD19
Precurser
Differentiating and identifiable cells with a given cell line
Granulocyte Colony Stimulating Factor G-CSF or Granuloctye-Monocyte Colony
Stimulating Factor
Stimulates the differentiation of a common myeloid progenitor cell into
grnaulocyte/monocyte, esonophil/basophil, megakaryocte/erythrocyte progenitor, or
mast cell then differentiation into their final form.
Erythropoietin (EPO)
produced by the kidney peritubular cells and stimulates the production of erythroblasts
in the bone marrow. CFU-E to pro-normoblasts.
Stem Cell Factor (SCF)
Kit- ligand binds to c-kit on hematopoietic stem cells to regulate stem cell differentiation
Interlukins
COMPLETE SOLUTIONS GRADED A++
Three phases of hematopoesis
Mesoblastic (yolk sac) phase
Hepatic
Medullary (Myeloid phase)
Mesoblastic (Yolk sac) phase
Phase that begins about 19 days after fertilization which includes erythroblast,
mesodermal cells, and hematopoeitic stems cells (HSCs), prodcution of hemaglobin
(Gower 1 and Gower 2), and formation of blood vessels by angioblasts.
Hepatic phase
Phase that begins around 4-5 week of gestation peaking around the 3rd month.
Primarily in the liver. Clusters of developing erythroblasts, granulocytes, and
monocytes. Begin definitive hematopoesis and production of HbF.
Medullary (Myeloid) phase
Phase that begins around 5 months of gestation and marrow becomes the primary site
of hematopoiesis. Myeloid to erythroid ratio is now 3:1. Extramedullary hematopoiesis
subsides. Less HbF, more HbA, HbA2
Hematopoietic tissue in adults
Thymus, lymph nodes, bonemarrow, liver, spleen
Active bone marrow location in adults
,Sternum, pelvis, ribs, vertebrae, skull, proximal ends of long bones.
Red Marrow
Hematopoietically active bone marrow
In all bones until the age of 7, bone marrow slowly is replaced by yellow marrow and is
then restricted to specific sites.
Yellow Marrow
Hematopoietically inactive. Adipocytes (fat cells)
Hematopoietic cords
Extravascular cords of the active red marrow between the spongy bone and trabeculae.
Forms the parenchyma of the bone marrow. Provides a lattice or meshwork (of reticular
cells) to support blood cell development. Productioin of cytokines, ahesive molecules,
steroid secretion (controls volume of bone marrow).
Increased red marrow
can be caused by leukemia and high altitude
Decreased red marrow
can be caused by aplastic anemia
Sinsusoids
Venous sinus (specialized vein) which provides venous drainage to the marrow. Has an
endothelial lining with a discontinuous basement membrane (collagen). Cells may leave
the marrow by enetering the parenchyma and move into the venous sinus to enter the
blood stream via the central vein.
Megakaryocytes
In bone marrow produces platelets
,Hematopoietic microenviornment
Protein carbohydrate matrix, adhesion molecules, cytokines (colony stimulating factors,
inteferons, interluekins, lymphokines
Extramedullary hematopoiesis
hematopoiesis that occurs outside of the bone marrow
Liver function in extramedullary hematopoiesis
Liver is the major site of hepatic phase/stage in which bone marrow is shut down/
inactive and the liver sequesters and removes damaged red blood cells. Often happens
as a result of porphyrias, hemolytic anemias, RBC dysplasia
Spleen function in hematopoiesis
Filters circulating blood
Lymph nodes in hematopoiesis
Site of B cell proliferation (germinal centers) and filtration of microrganisms
Thymus
Site of T cell condtioning
Stem Cell theory
Pluripotential stem cells give rise to all marrow cells.
Daughter cells either give rise to itself, or other daughter cell differentiates and matures.
Hematopoietic stem cells (HSC)
Cells charichterized by CD34 markers, no HLA-DR antigen, no antigens associated wih
more differentiated cells. Not morphologically identifiable.
Progenitor cell
, undifferentiated hematopoietic stem cell with a committed cell line, but not identifiable
morphologically.
Myeloid progenitor markers
CD33 CD38
Lymphoid progenitor markers
CD10 CD38
T- Lymphoid and NK cell progenitor markers
CD7
B-Lymphoid progenitor makers
CD19
Precurser
Differentiating and identifiable cells with a given cell line
Granulocyte Colony Stimulating Factor G-CSF or Granuloctye-Monocyte Colony
Stimulating Factor
Stimulates the differentiation of a common myeloid progenitor cell into
grnaulocyte/monocyte, esonophil/basophil, megakaryocte/erythrocyte progenitor, or
mast cell then differentiation into their final form.
Erythropoietin (EPO)
produced by the kidney peritubular cells and stimulates the production of erythroblasts
in the bone marrow. CFU-E to pro-normoblasts.
Stem Cell Factor (SCF)
Kit- ligand binds to c-kit on hematopoietic stem cells to regulate stem cell differentiation
Interlukins
