MLS Hematology Exam| 263 QUESTIONS| WITH COMPLETE SOLUTIONS

MLS Hematology Exam| 263 QUESTIONS| WITH COMPLETE SOLUTIONS What is the first type of cell produced by the developing embryo? Erythrocyte What percentage of tissue located in the bone marrow cavities of adults is fat? 50% Which of the following is not characteristic of pluripotent hematopoietic stem cells? Express the stem marker CD13 In an adult, what are the two best areas for obtaining active bone marrow by aspiration? Posterior iliac crest, sternum What is the normal ratio of myeloid to erythroid precursors in bone marrow (M:E ratio)? 4:1 Which of the following does not accurately describe hematopoietic growth factors? Action of majority is lineage restricted In the third month of gestation, what is the primary site of hematopoiesis? Liver The mechanism that relays information about tissue oxygen levels to erythropoietin-producing sites is located in the: Kidney Antigen-independent lymphopoiesis occurs in primary lymphoid tissue located in the: Thymus and bone marrow Programmed cell death is called: Apoptosis In what area of the bone marrow does hematopoiesis take place? Cords Bone marrow cellularity refers to the ration of: Hematopoietic tissue to adipose tissue Interleukins and colony stimulating factors are cytokines produced by: Monocytes and T lymphocytes What is the approximate total blood volume in an adult? 6 L The myeloid progenitor cell can produce cells committed to: Granulocytic, erythrocytic, monocytic, or megakaryocytic lineages The largest hematopoietic cells in normal bone marrow are: Megakaryocytes When evaluating a bone marrow aspirate smear, which finding is considered abnormal? The presence of 10% myeloblasts on the cell differential count As most blood cell lines mature, which of the following is characteristic? Nucleus to cytoplasm ratio (N:C) decreases Which of the following describes thrombopoietin (TPO)? Hormone produced by the liver that stimulates megakaryopoiesis When the hepatic phase of fetal life is reactivated in an adult, hematopoiesis can be termed: Myeloid metaplasia or extramedullary What is the average life span of a normal red blood cell? 120 days The Na+-K+ cation pump is an important mechanism in keeping the red blood cell intact. Its function is to maintain a high level of: Intracellular K+ Which of the following depicts the structure of the hemoglobin molecule? Four heme groups, four globin chains Which of the following describes the process known as culling? Removal of abnormal red cells by spleen Hemoglobin forms that are incapable of oxygen transport include: Carboxyhemoglobin and methemoglobin The majority of iron found in an adult is a constituent of: Hemoglobin A senescent red blood cell is one that has: Lived its life span What red cell morphologic abnormality is described by the term "poikilocytosis"? Deviations from normal shape Howell-Jolly bodies are composed of: DNA When spherocytes are reported, what is observed on the peripheral blood smear? Red cells without a central pallor The red cells found in lead poisoning characteristically exhibit coarse granules composed of __________ that are reported as _________. Aggregated ribosomes; basophilic stippling Rouleaux of red blood cells when seen in the monolayer of a blood smear is characteristic of: Multiple myeloma Which of the following is most frequently associated with the inclusion bodies seen in Color Plate 1? Post-splenectomy Which of the following statements about iron absorption is true? Absorption increases when erythropoietic activity increases What term describes a mature red blood cell that contains iron granules or deposits? Siderocyte Which of the following is associated with a "shift to the left" in the oxygen dissociation curve of hemoglobin? Decreased oxygen release Which of the following statements does not characterize erythropoietin (EPO)? Decreases stimulation of erythropoiesis when cellular hypoxia increases Which of the following factors will result in an immediate increase in oxygen delivery to the tissues? Increased hemoglobin binding of 2,3-BPG Periods of intense erythropoietin activity cause premature release of marrow reticulocytes into the blood. Which of the following is not true of these early reticulocytes? Loss of residual RNA occurs immediately upon marrow release Which of the following inclusions is only visible with supravital staining? Heinz bodies The presence of schistocytes on the peripheral blood smear is commonly associated with: Increased red cell destruction Which of the following may be a sign of accelerated bone marrow erythropoiesis? Nucleated red cells in the peripheral circulation Microcytic, hypochromic red cells are most often associated with impaired: Hemoglobin synthesis When in bone marrow, nucleated red cells present would be staged as: Orthochromic normoblasts When acanthocytes are found on the blood smear, it is usually the result of: Altered membrane lipids Which erythrocyte metabolic pathway generates adenosine triphosphate (ATP) via glycolysis? Embden-Meyerhof Which of the following red blood cell precursors is the last stage to undergo mitosis? Polychromatophilic normoblast The major adult hemoglobin requires the synthesis of alpha-globin chains and: Beta-globin chains Defective nuclear maturation commonly results in the production of red cells that are: Macrocytic The major storage form of iron is: Ferritin The red cells observed on a peripheral blood smear show extreme anisocytosis with an equal number of macrocytes and microcytes. Which of the following values correlate with this finding? MCV 90.0fL, RDW 25.0% Excessive extravascular red cell destruction is associated with: Bilirubinemia Which protein is primarily responsible for transport of hemoglobin dimers resulting from intravascular hemolysis? Haptoglobin The morphologic abnormality characteristically found in hemoglobinopathies is: Codocytes Where do the early and late stages of heme synthesis occur? In mitochondria Spectrin is a protein that occupies a major role in: Red cell membrane structure What is the function of reduced glutathione (GSH) in the red blood cell? Neutralizes intracellular oxidants that accumulate What does measuring the total iron binding capacity (TIBC) represent? Amount of iron that transferrin can bind Serum ferritin is a good indicator of the amount of: Storage iron Fetal hemoglobin differs from adult hemoglobin in that hemoglobin F: Resists elution from red cells with acid solutions Impaired DNA metabolism is characteristic of: Megaloblastic anemia Which of the following is associated with glucose-6-phosphate dehydrogenase (G6PD) deficiency? G6PD gene is located on the X chromosome In regard to variant hemoglobin E, alpha2 beta2 26Glu --- Lys, which of the following statements is false? Glutamic acid replaces lysine on position 26 of the beta chains The peripheral blood of a 16 year old female with a sporadic history of dizzy spells, fainting and jaundice. This patient also had a history of periodic abdominal pain related to gallstones. Upon physical exam, she exhibited mild splenomegaly. Her hemoglobin was 10.7 g/dL, hematocrit was 32%, red cell indices were normal and the direct antiglobulin test was negative. Based on history and peripheral blood morphology, which of the following statements is most likely true? An intrinsic hereditary defect of red cells should be suspected A 9 month old male was seen in the emergency department with a femur fracture that had occurred from a fall down the stairs. Upon physical exam, the physician noted hepatosplenomegaly, extreme pallor, and a slight arrhythmia. A complete blood count revealed the following: WBC = 12.2 x 10^3/uL RBC = 3.05 x 10^6/uL Hemoglobin = 6.1 g/dL Hematocrit = 20% MCV = 65.5 fL MCH = 20 pg MCHC = 30.5 g/dL RDW = 25% The Wright's stained blood smear showed the findings seen in Color Plate 4. Hemoglobin electrophoresis was ordered with results as follows: Hgb A = 0% Hgb A2 = 3% Hgb F = 97% Which condition is most likely causing the hematologic abnormalities? Cooley beta-thalassemia major A 14 year old African American male was seen in the clinic for abdominal pain. A complete blood count revealed the following: WBC = 7.0 x 10^3/uL RBC = 2.90 x 10^6/uL Hemoglobin = 8.5 g/dL Hematocrit = 25% MCV = 86.2 fL MCH = 29.3 pg MCHC = 34.0 g/dL RDW = 21% The peripheral smear showed the red blood cell morphology seen in Color Plate 5. What condition is suggested by these findings? Hemoglobin SC disease Pica is most commonly associated with which of the following conditions? Iron deficiency Of the following, the leading cause of folate deficiency is: Dietary insufficiency Which of the following statements about sickle cell syndromes is false? Hemoglobin S is more soluble in dithionite than is normal hemoglobin Schistocytes can be found in patients with microangiopathic hemolytic anemia (MAHA). Which of the following conditions could not be responsible for this type of red cell destruction? Idiopathic thrombocytopenic purpura (ITP) Which of the following blood findings does not correlate with the presence of ringed sideroblasts in the bone marrow? Increased total iron binding capacity Which of the following conditions is not usually associated with marked reticulocytosis? Pernicious anemia Hereditary stomatocytosis is manifested physiologically by changes in: Membrane cation permeability In addition to an increase in red blood cells, which of the following is characteristic of polycythemia vera? Increased platelets, increased granulocytes, decreased eryhthropoietin level Which of the following is not characteristic of aplastic anemia? Extramedullary hematopoiesis What values would you expect to obtain on hemoglobin and hematocrit determinations done immediately after a major hemorrhage, if hemoglobin and hematocrit values were normal prior to the hemorrhage? Both normal Results from a 1 day old infant include a hemoglobin of 20.1 g/dL, hematocrit of 60%, MCV of 110.2 fL and 4 nucleated red cells/100 WBCs. How should these results be interpreted? No further testing is indicated The red bloods cells with a single elongated projection are known as _______ and may be seen in _________.