AAB MT HEMATOLOGY EXAM 232 REAL EXAM
QUESTIONS WITH
100% CORRECT ANSWERS
What is hemoglobin composed of? - Ans--4 heme, 4 iron, 4 globins
What disorder does a defect in heme synthesis lead to? - Ans--Porphyria
Porphyria - Ans--Deficiency in the enzymes of the porphyrin pathway leads
to insufficient production of heme. The principal problem in these
deficiencies is the accumulation of porphyrins, the heme precursors, which
are toxic to tissue in high concentrations.
What is methemoglobin? - Ans--Methemoglobin is a form of hemoglobin
that contains ferric [Fe3+] iron and has a decreased ability to bind oxygen.
However, the ferric iron has an increased affinity for bound oxygen. When
methemoglobin concentration is elevated in red blood cells, tissue hypoxia
can occur.
What is the function of the enzyme methemoglobin-cytochrome C
reductase in a red blood cell? - Ans--To keep iron in the ferrous state
What product is formed when ferrous iron of hemoglobin is oxidized to the
ferric state? - Ans--Methemoglobin
What is carboxyhemoglobin? - Ans--A stable complex of carbon monoxide
and hemoglobin that forms in RBCs when carbon monoxide is inhaled or
produced in normal metabolism. Large quantities of it hinder delivery of O2
to the body. Tobacco smoking (through carbon monoxide inhalation) raises
the blood levels of COHb by a factor of several times from its normal
concentrations.
Which hemoglobin has a 200 times greater binding capacity for the
hemoglobin molecule than oxygen? - Ans--Carboxyhemoglobin
,Which hemoglobin derivative causes irreversible changes in RBCs? - Ans--
Sulfhemoglobin -- makes blood incapable of carrying oxygen.
Which of the following hemoglobins is NOT normally present in a normal
adult? - Ans--Hb-S
Which embryonic hemoglobin is normally found in newborns? - Ans--Hb-F
What is the most abundant hemoglobin in a newborn? - Ans--Hb-F
What is the molecular structure of Hemoglobin S? - Ans--Valine replaces
glutamic acid in the 6th position of the beta chain
Which of the following hemoglobins is insoluble under lowered oxygen
tension? - Ans--Hb-S
What laboratory test is used to confirm the specific diagnosis of sickle cell
anemia? - Ans--Hemoglobin electrophoresis
In the solubility test for hemoglobin S, what is the reagent responsible for the
reduction of the hemoglobin molecule? - Ans--Sodium dithionite
In hemoglobin C, what replaces glutamic acid? - Ans--Lysine
Which red blood cell inclusion is characteristic of hemoglobin C disease? -
Ans--Rod-shaped crystals
What is hemoglobin F composed of? - Ans--2 alpha and 2 gamma chains
Which hemoglobin is resistant to alkali denaturation? - Ans--Hb-F
Which hemoglobins are differentiated by the Kleihauer-Betke technique? -
Ans--Hb-A1 from Hb-F
What is the order of migration of hemoglobins, from fastest to slowest, on
cellulose acetate at pH 8.4? - Ans--A1, F, S, C
, Why is citrate agar used when abnormal hemoglobins are identified on
cellulose acetate at pH 8.6? - Ans--It separates hemoglobin S from
hemoglobin D
The cyanmethemoglobin method measures all hemoglobin pigments
EXCEPT which one? - Ans--Sulfhemoglobin
What is the diluent used in the cyanmethemoglobin method for the
determination of hemoglobin? - Ans--Drabkin's solution
What is the normal plasma hemoglobin concentration? - Ans--2-3 mg/dL
Which plasma protein binds free hemoglobin? - Ans--Haptoglobin
Which one of the following statements concerning hemolytic anemia is
false? - Ans--The serum haptoglobin is increased
In this type of anemia RBCs are normocytic and normochromic. RBCs,
hemoglobin, and hematocrit are decreased and the indirect bilirubin is
increased. - Ans--Hemolytic anemia
Myoglobin can be separated from hemoglobin by saturating the specimen
with which one of the following reagents? - Ans--Ammonium sulfite
The hematocrit is also known as which one of the following terms? - Ans--
Packed red blood cell volume
The degree of packing of cells during centrifugation depends on all of the
following EXCEPT which one? - Ans--Bore size of the microhematocrit tube
The degree of packing of cells during centrifugation depends on all of the
following: - Ans--Speed of the centrifugation, radius of centrifugation, and
time of centrifugation.
During examination of a spun hematocrit, in which layer are the white blood
cells found? - Ans--Buffy coat
QUESTIONS WITH
100% CORRECT ANSWERS
What is hemoglobin composed of? - Ans--4 heme, 4 iron, 4 globins
What disorder does a defect in heme synthesis lead to? - Ans--Porphyria
Porphyria - Ans--Deficiency in the enzymes of the porphyrin pathway leads
to insufficient production of heme. The principal problem in these
deficiencies is the accumulation of porphyrins, the heme precursors, which
are toxic to tissue in high concentrations.
What is methemoglobin? - Ans--Methemoglobin is a form of hemoglobin
that contains ferric [Fe3+] iron and has a decreased ability to bind oxygen.
However, the ferric iron has an increased affinity for bound oxygen. When
methemoglobin concentration is elevated in red blood cells, tissue hypoxia
can occur.
What is the function of the enzyme methemoglobin-cytochrome C
reductase in a red blood cell? - Ans--To keep iron in the ferrous state
What product is formed when ferrous iron of hemoglobin is oxidized to the
ferric state? - Ans--Methemoglobin
What is carboxyhemoglobin? - Ans--A stable complex of carbon monoxide
and hemoglobin that forms in RBCs when carbon monoxide is inhaled or
produced in normal metabolism. Large quantities of it hinder delivery of O2
to the body. Tobacco smoking (through carbon monoxide inhalation) raises
the blood levels of COHb by a factor of several times from its normal
concentrations.
Which hemoglobin has a 200 times greater binding capacity for the
hemoglobin molecule than oxygen? - Ans--Carboxyhemoglobin
,Which hemoglobin derivative causes irreversible changes in RBCs? - Ans--
Sulfhemoglobin -- makes blood incapable of carrying oxygen.
Which of the following hemoglobins is NOT normally present in a normal
adult? - Ans--Hb-S
Which embryonic hemoglobin is normally found in newborns? - Ans--Hb-F
What is the most abundant hemoglobin in a newborn? - Ans--Hb-F
What is the molecular structure of Hemoglobin S? - Ans--Valine replaces
glutamic acid in the 6th position of the beta chain
Which of the following hemoglobins is insoluble under lowered oxygen
tension? - Ans--Hb-S
What laboratory test is used to confirm the specific diagnosis of sickle cell
anemia? - Ans--Hemoglobin electrophoresis
In the solubility test for hemoglobin S, what is the reagent responsible for the
reduction of the hemoglobin molecule? - Ans--Sodium dithionite
In hemoglobin C, what replaces glutamic acid? - Ans--Lysine
Which red blood cell inclusion is characteristic of hemoglobin C disease? -
Ans--Rod-shaped crystals
What is hemoglobin F composed of? - Ans--2 alpha and 2 gamma chains
Which hemoglobin is resistant to alkali denaturation? - Ans--Hb-F
Which hemoglobins are differentiated by the Kleihauer-Betke technique? -
Ans--Hb-A1 from Hb-F
What is the order of migration of hemoglobins, from fastest to slowest, on
cellulose acetate at pH 8.4? - Ans--A1, F, S, C
, Why is citrate agar used when abnormal hemoglobins are identified on
cellulose acetate at pH 8.6? - Ans--It separates hemoglobin S from
hemoglobin D
The cyanmethemoglobin method measures all hemoglobin pigments
EXCEPT which one? - Ans--Sulfhemoglobin
What is the diluent used in the cyanmethemoglobin method for the
determination of hemoglobin? - Ans--Drabkin's solution
What is the normal plasma hemoglobin concentration? - Ans--2-3 mg/dL
Which plasma protein binds free hemoglobin? - Ans--Haptoglobin
Which one of the following statements concerning hemolytic anemia is
false? - Ans--The serum haptoglobin is increased
In this type of anemia RBCs are normocytic and normochromic. RBCs,
hemoglobin, and hematocrit are decreased and the indirect bilirubin is
increased. - Ans--Hemolytic anemia
Myoglobin can be separated from hemoglobin by saturating the specimen
with which one of the following reagents? - Ans--Ammonium sulfite
The hematocrit is also known as which one of the following terms? - Ans--
Packed red blood cell volume
The degree of packing of cells during centrifugation depends on all of the
following EXCEPT which one? - Ans--Bore size of the microhematocrit tube
The degree of packing of cells during centrifugation depends on all of the
following: - Ans--Speed of the centrifugation, radius of centrifugation, and
time of centrifugation.
During examination of a spun hematocrit, in which layer are the white blood
cells found? - Ans--Buffy coat
