17 Flashcards
- The common denominator in the hemoglobinopathies is that all are
A. structural defects in the erythrocyte membrane
B. metabolic defects in the erythrocytic physiology
C. inherited or genetic defects related to hemoglobin
D. acquired defects related to hemoglobin
C. inherited or genetic defects related to hemoglobin
- Hemoglobinopathies can be classified as
A. abnormal hemoglobin globulin structure
B. a defect of hemoglobin globulin synthesis
C. a combination of defects of both structure and synthesis
D. all of the above
D. all of the above
- Normal adult hemoglobin contains the following components: Hb A (95% to 98%), Hb A2 (2% to 3%), Hb A1 (3% to 6%), and Hb F (less than 1%).
A. True
B. False
A. True
- In the hemoglobinopathies, a trait is described as
A. heterozygous and asymptomatic
B. heterozygous and symptomatic
C. homozygous and asymptomatic
D. homozygous and symptomatic
A. heterozygous and asymptomatic
- In sickle cell disease, the cause is
A. a change of a single nucleotide (GAT to GTT)
B. the substitution of valine for glutamic acid at the sixth position on the beta chain of the hemoglobin molecule
C. not genetic
D. both A and B
D. both A and B
In sickle cell disease, the abnormality is related to
A. the rate of synthesis of hemoglobin
B. an abnormal molecular structure of hemoglobin
C. an acquired defect
D. a membrane dysfunction
B. an abnormal molecular structure of hemoglobin
One of the two most common monogenetic diseases of man is
A. sickle cell trait
B. sickle cell disease
C. α thalassemia
D. Hb SC disease
B. sickle cell disease
- If a patient with sickle cell disease is in an acute crisis state, peripheral blood smears may exhibit
A. leptocytes
B. drepanocytes
C. ovalocytes
D. stomatocytes
B. drepanocytes
- What estimated percentage of black Americans are heterozygous for Hb S?
A. 4%
B. 8%
C. 12%
D. More than 25%
B. 8%
What factors contribute to the sickling of erythrocytes in sickle cell disease crisis?
A. Increase in blood pH and increase in oxygen.
B. Extremely hot weather.
C. Extremely reduced oxygen and increased acidity in the blood.
D. Sickling is spontaneous.
C. Extremely reduced oxygen and increased acidity in the blood.
The most common complaint associated with sickle cell disease?
A. Acute pain
B. Organ or tissue failure
C. Stroke
D. All of the above
A. Acute pain
Thalassemias are characterized by
A. abnormal amino acid sequence of the hemoglobin molecules
B. defective iron synthesis
C. absence or decrease in synthesis of one or more globulin subunits
D. skeletal membrane defects
C. absence or decrease in synthesis of one or more globulin subunits
Homozygous β thalassemia patients have
A. no manifestations of anemia
B. only mild anemia
C. moderate anemia
D. severe transfusion-dependent anemia
D. severe transfusion-dependent anemia
In α-type thalassemia, with three inactive α genes, which of the following is characteristic?
A. Hb A2
B. Hb A
C. Hb H
D. Hb F and A2
C. Hb H
What is the primary risk to thalassemia major patients who receive frequent and multiple blood transfusions?
A. Iron overload
B. Citrate toxicity
C. Polycythemia
D. Hyperviscosity
A. Iron overload
The peripheral blood smear in silent-state patients with α thalassemia typically appears as
A. normochromic, normocytic
B. microcytic, hypochromic
C. macrocytic, normocytic
D. macrocytic, hypochromic
A. normochromic, normocytic
The characteristic hemoglobin concentration in a patient’s silent state with heterozygous β thalassemia is
A. Hb A level normal
B. Hb A2 increased
C. Hb A2 level decreased
D. Hb F level increased
A. Hb A level normal
Deoxyhemoglobin C has
A. decreased solubility
B. increased solubility
C. the ability to form intracellular crystals
D. both A and C
D. both A and C
The incidence of Hb E hemoglobinopathy is highest in
A. Southeast Asia
B. China
C. Vietnam
D. Native Americans
A. Southeast Asia
Most unstable hemoglobins
A. are inherited autosomal dominant disorders
B. result from amino acid substitutions or deletions
C. are hemoglobin variants
D. all of the above
D. all of the above
