UAMS HEMATOLOGY ACTUAL EXAM 1 QUESTIONS

UAMS HEMATOLOGY (ACTUAL / ) EXAM 1 QUESTIONS

AND VERIFIED ANSWERS

Isotonic saline because it will not lyse RBCs because it has the

same pH as blood. 1:100. - --Answers---What is the typical

diluting fluid for manual RBC counts and why? What is the dilution factor?

1% ammonium oxalate. 1:100. - --Answers---What is the typical

diluting fluid for platelet counts? What is the dilution factor?

It is done by electronic cell impedance. A vacuum pulls WBCs and platelets through one chamber and RBCs through another.Cells are poor conductors so the current gets interrupted and the changes in voltage are recorded.Blood is focused to a single file. Cells interrupt the laser light path and are counted as they come by. - --Answers---What is the Coulter principle when it comes to automated counting?What is the light or optical scatter principle when it comes to automated counting?

Erythroid cells do not have granules whatsoever. Myeloid cells begin to have granules starting with the promyelocyte.Precursor erythroid cells have navy blue or royal blue cytoplasm that becomes salmon pink. Myeloid cells have grayish blue or light blue cytoplasm that becomes pink. - -- Answers---What are the biggest differences between myeloid and erythroid cells? 1 / 3

To carry O2 from the lungs to the tissues in the form of hemoglobin and return CO2 to the lungs, buffering blood pH. - --Answers---What is the primary responsibility of RBCs?

In the bone marrow - --Answers---Where does erythropoiesis occur?

CFU-GEMM gives rise to BFU-E which leads to a large multiclustered colony which develops into CFU-E.CFU-E has many receptor sites for EPO and proliferates into pronormablasts which is the first recognizable erythrocyte precursor in the bone marrow. - --Answers---What are the cytokines for erythropoiesis? Once the final cytokine has been reached, what happens?

Erythropoietin. It is produced by the kidneys primarily but can be produced by the liver in small amounts. It is produced due to stimulation due to oxygen tension in the blood. It prevents apoptosis of erythroid precursors, induces hemoglobin synthesis, and is a differentiation factor that causes CFU-E to differentiate into pronormoblasts. - --Answers---What is EPO and what does it do?

Pronormoblasts which are the nucleated erythrocyte precursors. Reticulocytes which are young erythrocytes with residual RNA but no nucleus are released into the blood to circulate for 1-2 before becoming mature RBCs. - --Answers-- 2 / 3

-What are the erythroid precursors in the bone marrow and when are they released?

Cell size decreases, loss of nucleoli, nucleus is condensed and expelled, and cytoplasm changes from dark blue to orange/red. - --Answers---What are the characteristics of RBC maturation?

Pronormoblast or rubriblast - --Answers---What is the earliest recognizable RBC that is characterized by navy or royal blue cytoplasm?

Basophilic pronormoblast or prorubricyte - --Answers--- Which RBC is characterized by a perinuclear halo?

Polychromatic pronormoblast or rubricyte - --Answers--- Which RBC is characterized by an eccentric nucleus and light gray blue cytoplasm?

Orthochromatic pronormoblast or metarubricyte - --Answers- --Which RBC is characterized by a small, dense nucleus that is extremely close to the side?

Polychromatic erythrocyte or reticulocyte. An RBC cannot be called a reticulocyte until it has been stained with new methylene blue and ribosomes containing residual RNA show up. - --Answers---Which RBC is characterized by a diffuse basophilic cytoplasm and no nucleus? When does this RBC become "official?"

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