AAB MT HEMATOLOGY EXAM SCRIPT 2026 PRACTICE QUESTIONS WITH
COMPLETE SOLUTIONS VERIFIED 100, Exams of Reasoning
What is hemoglobin composed of? - ANSWER4 heme, 4 iron, 4 globins
What disorder does a defect in heme synthesis lead to? - ANSWERPorphyria
Porphyria - ANSWERDeficiency 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? - ANSWERMethemoglobin 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? - ANSWERTo keep iron in the ferrous state
What product is formed when ferrous iron of hemoglobin is oxidized to the
ferric state? - ANSWERMethemoglobin
What is carboxyhemoglobin? - ANSWERA 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? - ANSWERCarboxyhemoglobin
Which hemoglobin derivative causes irreversible changes in RBCs? -
ANSWERSulfhemoglobin -- makes blood incapable of carrying oxygen.
Which of the following hemoglobins is NOT normally present in a normal
adult? - ANSWERHb-S
Which embryonic hemoglobin is normally found in newborns? - ANSWERHb-F
What is the most abundant hemoglobin in a newborn? - ANSWERHb-F
What is the molecular structure of Hemoglobin S? - ANSWERValine replaces
glutamic acid in the 6th position of the beta chain
Which of the following hemoglobins is insoluble under lowered oxygen
tension? - ANSWERHb-S
What laboratory test is used to confirm the specific diagnosis of sickle cell
anemia? - ANSWERHemoglobin electrophoresis
, In the solubility test for hemoglobin S, what is the reagent responsible for the
reduction of the hemoglobin molecule? - ANSWERSodium dithionite
In hemoglobin C, what replaces glutamic acid? - ANSWERLysine
Which red blood cell inclusion is characteristic of hemoglobin C disease? -
ANSWERRod-shaped crystals
What is hemoglobin F composed of? - ANSWER2 alpha and 2 gamma chains
Which hemoglobin is resistant to alkali denaturation? - ANSWERHb-F
Which hemoglobins are differentiated by the Kleihauer-Betke technique? -
ANSWERHb-A1 from Hb-F
What is the order of migration of hemoglobins, from fastest to slowest, on
cellulose acetate at pH 8.4? - ANSWERA1, F, S, C
Why is citrate agar used when abnormal hemoglobins are identified on
cellulose acetate at pH 8.6? - ANSWERIt separates hemoglobin S from
hemoglobin D
The cyanmethemoglobin method measures all hemoglobin pigments EXCEPT
which one? - ANSWERSulfhemoglobin
What is the diluent used in the cyanmethemoglobin method for the
determination of hemoglobin? - ANSWERDrabkin's solution
COMPLETE SOLUTIONS VERIFIED 100, Exams of Reasoning
What is hemoglobin composed of? - ANSWER4 heme, 4 iron, 4 globins
What disorder does a defect in heme synthesis lead to? - ANSWERPorphyria
Porphyria - ANSWERDeficiency 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? - ANSWERMethemoglobin 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? - ANSWERTo keep iron in the ferrous state
What product is formed when ferrous iron of hemoglobin is oxidized to the
ferric state? - ANSWERMethemoglobin
What is carboxyhemoglobin? - ANSWERA 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? - ANSWERCarboxyhemoglobin
Which hemoglobin derivative causes irreversible changes in RBCs? -
ANSWERSulfhemoglobin -- makes blood incapable of carrying oxygen.
Which of the following hemoglobins is NOT normally present in a normal
adult? - ANSWERHb-S
Which embryonic hemoglobin is normally found in newborns? - ANSWERHb-F
What is the most abundant hemoglobin in a newborn? - ANSWERHb-F
What is the molecular structure of Hemoglobin S? - ANSWERValine replaces
glutamic acid in the 6th position of the beta chain
Which of the following hemoglobins is insoluble under lowered oxygen
tension? - ANSWERHb-S
What laboratory test is used to confirm the specific diagnosis of sickle cell
anemia? - ANSWERHemoglobin electrophoresis
, In the solubility test for hemoglobin S, what is the reagent responsible for the
reduction of the hemoglobin molecule? - ANSWERSodium dithionite
In hemoglobin C, what replaces glutamic acid? - ANSWERLysine
Which red blood cell inclusion is characteristic of hemoglobin C disease? -
ANSWERRod-shaped crystals
What is hemoglobin F composed of? - ANSWER2 alpha and 2 gamma chains
Which hemoglobin is resistant to alkali denaturation? - ANSWERHb-F
Which hemoglobins are differentiated by the Kleihauer-Betke technique? -
ANSWERHb-A1 from Hb-F
What is the order of migration of hemoglobins, from fastest to slowest, on
cellulose acetate at pH 8.4? - ANSWERA1, F, S, C
Why is citrate agar used when abnormal hemoglobins are identified on
cellulose acetate at pH 8.6? - ANSWERIt separates hemoglobin S from
hemoglobin D
The cyanmethemoglobin method measures all hemoglobin pigments EXCEPT
which one? - ANSWERSulfhemoglobin
What is the diluent used in the cyanmethemoglobin method for the
determination of hemoglobin? - ANSWERDrabkin's solution
