B4M1 23-24 Flashcards
Which essential property of hematopoietic stem cells is required to avoid stem cell depletion?
A. Self-renewal
B. Pluripotency
C. Restricted differentiation potential
D. Commitment to specialized cell population
A. Self-renewal
Which of the following characteristics best describes Interleukin-3 ?
A. It induces growth for specific types of stem cells.
B. It is controlled by factors outside the bone marrow.
C. It promotes growth of all types of stem cells.
D. It causes one type of stem cell to differentiate.
C. It promotes growth of all types of stem cells.
Which stage is the last nucleated erythrocyte stage in the maturation of red cells?
A. Reticulocyte
B. Rubricyte
C. Rubriblast
D. Metarubricyte
D. Metarubricyte
If eosinophils function to kill helminthic and other parasites, which of the following is a
function of basophils?
A. kill bacteria
B. phagocytose virus
C. regulate adaptive immunity
D. release histamine during allergy
D. release histamine during allergy
Which of the following statements correctly describes the general features of eosinophils?
A. Once eosinophils migrate to the tissues, they are able to return to the peripheral circulation.
B. From the blood, eosinophils move towards areas localized in the inner most organs.
C. The half life of eosinophils in blood is about 4 hours.
D. The highest eosinophil counts occur early in the morning.
A. Once eosinophils migrate to the tissues, they are able to return to the peripheral circulation.
Which of the following characteristics must an erythrocyte membrane possess to be effective
in hemoglobin delivery?
A. It is able to change in shape.
B. It is firm and strong.
C. It is thick and rounded.
D. It is round and coarse.
A. It is able to change in shape.
A person who lives in high attitudes will have increased red blood cell production due to
increased production of a hormone that comes from which of the following organs:
A. Liver
B. Bone marrow
C. Spleen
D. Kidney
D. Kidney
Which of the following differentiates the granules found in eosinophils to those found in
neutrophils?
A. The presence of peroxidase.
B. The presence of phagocytic and bactericidal cationic proteins.
C. The lack of lysozyme.
D. The lack of B-glucuronidase.
C. The lack of lysozyme.
What is the principal growth factor for basophilic growth?
A. IL-1
B. GM-CSF
C. Eosinophilic factor A
D. IL-3
D. IL-3
Which of the following is the leukocyte picture seen in starvation?
A. Neutrophilia
B. Neutropenia
C. Lymphocytosis
D. Lymphopenia
B. Neutropenia
D. Lymphopenia
AZ, 6 years old, female, was so excited because it was the first time she tried crabs for
dinner. After a few minutes of eating crabs, she suddenly felt abdominal pain and developed
shortness of breath. At the ER, AZ was noted to have urticaria. The physician ordered a CBC
test. Which of the following would be seen in the CBC results?
A. Neutrophilia
B. Lymphocytosis
C. Basophilia
D. Presence of band cells and monocytosis
C. Basophilia
Which statement best describes agranulocytes?
A. They are characterized by the presence of large cytoplasmic granules.
B. They lack visible cytoplasmic granules under a light microscope.
C. They are primarily involved in allergic reactions and histamine release.
D. They are the most abundant type of white blood cells in the human body.
B. They lack visible cytoplasmic granules under a light microscope.
Which of the following is the characteristic morphology of a monocyte?
A. Small, round cell with a large round nucleus and a small amount of cytoplasm
B. Large cell with a kidney-shaped or horseshoe-shaped nucleus and abundant cytoplasm
C. Small cell with a multilobed nucleus and abundant cytoplasmic granules
D. Large cell with a single round nucleus and minimal cytoplasmic volume
B. Large cell with a kidney-shaped or horseshoe-shaped nucleus and abundant cytoplasm
Which of the following statements accurately describes the physiologic purpose of functional
circulating fragments of megakaryocytes?
A. maintain the integrity of blood volume
B. form hemodynamic plugs
C. accelerate blood loss from injured vessels
D. promote coagulation of plasma factors
D. promote coagulation of plasma factors
The chromatin observed when viewing a megakaryocyte under high magnification is
characterized to have which distinctive pattern?
A. scattered and hazy
B. pyknotic with central condensation
C. fine and concentric
D. linear and coarse
D. linear and coarse
Which part of a complete blood count (CBC) calculates the blood’s red blood cell
percentage?
A. Hemoglobin
B. Hematocrit
C. Leukocytes
D. Blood components
B. Hematocrit
Which is the role of platelets in the process of blood clotting?
A. Platelets play a crucial role in blood clotting by forming a plug at the site of injury, releasing
clotting factors, and promoting the formation of fibrin strands to stabilize the clot.
B. The creation of collagen strands to stabilize the clot, the release of clotting factors, and the
formation of a plug at the site of injury are all ways in which platelets contribute significantly to
blood clotting.
C. Platelets regulate blood vessel hemostasis by dilatation of blood vessels to prevent blood
from leaking.
D. Platelets normally take 1-2 hours to adhere to the injured site to promote blood clotting.
A. Platelets play a crucial role in blood clotting by forming a plug at the site of injury, releasing
In order to directly compute for the Mean Corpuscular Volume (MCV), which of the following
data would you directly need?
A. Hematocrit and white blood cell count
B. Hemoglobin and platelet count
C. Hematocrit and red blood cell count
D. Hemoglobin and mean corpuscular volume concentration
C. Hematocrit and red blood cell count
You were interpreting results of a patient’s complete blood count and noted that there is a
reduction of the absolute neutrophil count (ANC). What would occur as a direct result?
A. Lymphocytosis
B. Neutropenia
C. Monocytosis
D. Decreased Platelet Count
B. Neutropenia
I. 2 succinyl-CoA + 2 glycine → pyrrole
II. 4 pyrrole → protoporphyrin IX
III. protoporphyrin IX + Fe++ → heme
IV. heme + polypeptide → hemoglobin chain (α or β)
V. 2 α chains + 2 β chains → hemoglobin A
In the figure shown above, which step is considered the rate-limiting step in the synthesis of
hemoglobin?
A. V
B. IV
C. I
D. III
C. I
What would result if formation of complexes with metal ions bound to the nitrogen atom of
the pyrrole rings occurs?
*A. Formation of porphyrin
B. Formation of isomeric proteins
C. Conformational changes in a polypeptide chain
D. Construction of a tetramer
A. Formation of porphyrin
Which of the following is the biochemical structure of hemoglobin composed of?
A. 2 units of succinyl-coA and 2 units of glycine
B. Protoporphyrin IX and ferrous iron
*C. 4 polypeptide heme chains
D. 2 different polypeptide units forming a pentamer
C. 4 polypeptide heme chains
This form of hemoglobin has lost its capacity to carry oxygen and carbon dioxide due to the
oxidation of iron from ferrous state to the ferric state:
A. Carboxyhemoglobin
B. Hemoglobin
*C. Methemoglobin
D. Sulfhemoglobin
C. Methemoglobin
In the chemistry of hemoglobin, it is pointed out that O2 molecules combine loosely and
reversibly with the heme portion of hemoglobin. When PO2 is _______ as in the pulmonary
capillaries, O2 _______ with hemoglobin.
A. low, binds
*B. high, binds
C. low, unbinds
D. high, unbinds
B. high, binds
This behavior of hemoglobin permits hemoglobin to maximize both the quantity of O2
loaded at the PO2 of the lungs and the quantity of O2 released at the PO2 of the peripheral
tissues
A. Hemoglobin hydration
B. Hemoglobin transition
C. Cooperative transition
*D. Cooperative binding
D. Cooperative binding
Which types of globin chains are the most common and form adult hemoglobin?
A. Alpha and lambda
B. Alpha and gamma
C. Alpha and delta
*D. Alpha and beta
D. Alpha and beta
Which of the following correctly describes the most important feature of hemoglobin?
A. Its ability to transform molecular oxygen to ionic oxygen
*B. Its ability to combine loosely and reversibly with oxygen
C. Its ability to deliver oxygen to hypoxic tissues
D. Its ability to gather oxygen and deliver to hypoxic tissues
B. Its ability to combine loosely and reversibly with oxygen
Which of the following correctly describes lymphocytes?
A. B cells are a minor population (30% to 40% of the lymphocytes), probably have a short life
span measured in days (with the exception of memory B cells), and are distinguished by the
presence of considerable immunoglobulin on their surface membranes.
B. Majority of circulating lymphocytes are B cells that have a life span of months to years.
C. B cells are a major population (60% to 80% of the lymphocytes), probably have a short life
span measured in days (with the exception of memory B cells), and are distinguished by the
presence of considerable immunoglobulin on their surface membranes.
*D. Majority of circulating lymphocytes are T cells that have a life span of months to years.
D. Majority of circulating lymphocytes are T cells that have a life span of months to years.
How do eosinophils function during a parasitic infection?
A. They generate reducing agents which are toxic to helminths..
B. They mediate immediate hypersensitivity reactions.
C. They express chemokine receptor CCRE.
*D. They release cationic proteins and oxidants from granules.
D. They release cationic proteins and oxidants from granules.
Which of the following is the rate limiting factor in causing blood coagulation?
A. Formation of prothrombin activator
B. Sufficient amount of ionic Calcium
C. Conversion of prothrombin to thrombin
D. Polymerization of fibrinogen molecules into fibrin fibers
A. Formation of prothrombin activator
This coagulation factor belongs to the Vitamin K dependent group and needs this vitamin for
its synthesis in the liver:
A. Proaccelerin
B. Proconvertin
C. Plasma thromboplastin antecedent
D. Fibrin stabilizing factor
B. Proconvertin
It is a single chain Υ globulin produced in the liver and is present in the serum:
A. Fibrinogen
*B. Prekallikrein
C. Anti-hemophilic B factor
D. Hageman factor
This factor is a lipoprotein found in most tissues of the body, with an increased
concentration in the lungs and brain:
A. III
B. IV
C. V
D. VII
A. III
Among the substances listed below, which one is an anticoagulant?
A. Thrombomodulin
B. Platelet phospholipids
C. Thromboplastin
D. Prothrombin
A. Thrombomodulin
Glycocalyx, a mucopolysaccharide adsorbed to the surface of the endothelium, exerts its
intravascular anticoagulant property by:
A. removing thrombin from the blood.
B. preventing contact activation of the intrinsic clotting system.
C. inactivating activated Factors V and VIII.
D. repelling clotting factors, preventing clotting activation.
D. repelling clotting factors, preventing clotting activation.
While reviewing for a module quiz in Hematology, your 12-year old sister asked you why
blood normally does not clot inside the blood vessels. Which of the following explanations would
correctly answer her question?
A. Presence of abundant heparin, which is an anticoagulant, in the vascular system
B. The plasma contains a large amount of circulating plasmin that digests the clot.
C. The rapid flow of blood inside the blood vessels instantly dislodges the clot.
D. Due to the smooth endothelium, adsorbed glycocalyx and thrombomodulin
D. Due to the smooth endothelium, adsorbed glycocalyx and thrombomodulin
When a blood vessel is injured, prevention of major blood loss is achieved by clot or
thrombus formation. Upon healing of the injured blood vessel, the thrombus is lysed through:
A. Polymerization which converts insoluble fibrinogen to soluble fibrin.
B. Activation of plasminogen to plasmin by tissue plasminogen activator.
C. The catalytic action of thrombin in cleaving small peptides from fibrin.
D. Activation of the series of serine protease-mediated cleavage events.
B. Activation of plasminogen to plasmin by tissue plasminogen activator.
APTT is used to assess the intrinsic coagulation mechanism, by measuring which of the
following factors?
A. Factor XIII
B. Factor III
C. Factor VII
D. Factor VIII
D. Factor VIII
A patient with low levels of fibrinogen undergoes a capillary fragility test. Which of the
following would indicate a positive result?
A. Whitening of the forearm
B. Very few amounts of petechiae above the pressure point
C. Numerous petechiae in the forearm
D. Moderate amount of paresthesia at the forearm region
C. Numerous petechiae in the forearm
What is the most important in-vivo activator of Factor X?
A. Factor VIIa + Tissue Factor complex
B. Factor IXa + Factor VIIIa complex
C. Factor VIIIa + Tissue Factor complex
D. Factor IXa + Factor VIIa complex
B. Factor IXa + Factor VIIIa complex
Heme is synthesized by the incorporation of ferrous ion (Fe++) into protoporphyrin III being
catalyzed by the enzyme:
A. Ferroxidase
B. Ferrochelatase
C. Ferroreductase
D. Ferroamidase
B. Ferrochelatase
Where does heme synthesis occur?
A. Cytoplasm
B. Ribosomes
C. Membrane
D. Mitochondrial matrix
D. Mitochondrial matrix
The committed step for the synthesis of heme is catalyzed by which enzyme?
A. Reductase
B. Oxidase
C. Synthase
D. Lyase
C. Synthase
By weight, which of the following is the major location of heme synthesis:
A. Liver
B. Intestines
C. Stomach
D. Mouth
A. Liver
Which of the following amino acids is the starting material for heme synthesis?
A. Aspartate
B. Glutamine
C. Glycine
D. Histidine
C. Glycine
Which of the following is the first hemostatic response to blood vessel injury?
A. Growth of fibrous tissue
B. Formation of platelet plug
C. Blood clot production
D. Vascular constriction
D. Vascular constriction
With normally functioning platelets, at which level is spontaneous bleeding generally
expected?
A. Platelet count of >50,000 -100,000 per microliter
B. Platelet count of 20,000 - 50,000 per microliter
C. Platelet count of <20,000 per microliter
D. Platelet count of <10,000 per microliter
C. Platelet count of <20,000 per microliter
Factor X is also known as:
A. Prothrombin
B. Stuart-Prower Factor
C. Hageman Factor
D. Tissue Factor
B. Stuart-Prower Factor
Which of the following events is generally associated with primary hemostasis?
A. Endothelin release
B. Platelet activation
C. Fibrin polymerization
D. Release of thrombomodulin
B. Platelet activation
Secondary hemostasis refers to _____ at the site of injury.
A. formation of platelet plug
B. arteriolar vasoconstriction
C. clot stabilization
D. deposition of fibrin
D. deposition of fibrin
