Deck 6: Hemoglobin

Question 1

Which of the following is a laboratory test that can be used to identify the occurrence of intravascular hemolysis?

A) Prussian blue stain of renal tubular cells
B) Nitric oxide concentration
C) Chloride shift
D) Isoelectric focusing

Answer 1

Prussian blue stain of renal tubular cells

Question 2

Which of the following is considered a normal hemoglobin concentration in an adult?

A) 9.1 g/dL
B) 1.8 g/dL
C) 21.2 g/dL
D) 14.8 g/dL

Answer 2

14.8 g/dL

Question 3

How is globin chain production regulated in the body?

A) By regulating the amount of heme produced
B) By regulating the amount of iron incorporated into the heme moiety
C) By regulating the number of RBCs produced
D) By regulating the rate of transcription for protein synthesis

Answer 3

By regulating the rate of transcription for protein synthesis

Question 4

An elevated hemoglobin A1C indicates that:

A) The patient has an elevated hemoglobin
B) The patient is anemic
C) The patient's RBCs have been exposed to an elevated blood glucose for a prolonged period of time
D) The patient's RBCs need glucose

Question 5

Which of the following is responsible for incorporating iron into the heme molecule?

A) ALA dehydrase
B) PBG deaminase
C) Uroporphyrinogen III
D) Ferrochelatase

Question 6

Which of the following conditions produces a favorable environment for hemoglobin to bind to oxygen? (Normal body temperature is <100°F; normal blood pH: 7.35-7.45.)

A) A body temperature of 102°F
B) A high 2,3-BPG concentration
C) A blood pH of 7.31
D) High PO₂

Question 7

When mutations occur in the globin chains of hemoglobin, what two interactions can be impaired?

A) Stability and hemoglobin-oxygen affinity
B) Iron binding and stability
C) Heme synthesis and affinity
D) Iron regulation and affinity

Question 8

What are the chain designations for hemoglobin F?

A) α₂β₂
B) α₂δ₂
C) α₂γ₂
D) α₂ε₂

Question 9

Fetal hemoglobin is composed of what two globin chains?

A) Two alpha, two beta
B) Two alpha, two gamma
C) Two alpha, two delta
D) Four gamma

Question 10

Which of the following is an expression of the oxygen affinity of hemoglobin?

A) Oxyhemoglobin
B) Deoxyhemoglobin
C) PCO₂
D) P50

Question 11

In the complete hemoglobin structure, iron is:

A) Attached to the alpha-globin chains
B) Attached to the non-alpha-globin chain
C) In the mitochondria
D) In the protoporphyrin ring

Question 12

The majority of carbon dioxide is transported in the body:

A) By dissolving in plasma
B) As carbonic acid
C) By binding to hemoglobin
D) As methemoglobin

Question 13

High concentrations of heme would cause which of the following?

A) A decrease in the synthesis of ALA
B) An increase in globin chain production
C) A decrease in globin chain production
D) An increase in ferrochelatase

Question 14

Which non-alpha-globin chain composes the predominating normal hemoglobin in adults?

A) Gamma
B) Delta
C) Beta
D) Zeta

Question 15

The measurement of glycosylated hemoglobin is used as an indicator of what disease process?

A) Anemia
B) Oxygen affinity
C) Cyanosis
D) Diabetes

Question 16

A high concentration of H+ ions will have what kind of effect on the oxygen dissociation curve?

A) A shift to the left
B) No effect on the oxygen dissociation curve
C) A shift to the right
D) Cannot be determined based on information given

Question 17

To regulate the amount of heme produced, what enzyme must be regulated?

A) ALAS
B) PBG deaminase
C) Uroporphyrinogen III
D) Ferrochelatase

Question 18

During extravascular hemolysis, which of the following hemoglobin components are physiologically recycled?

A) Iron and heme
B) Haptoglobin and heme
C) Iron and globin
D) Heme and globin

Question 19

What structure within hemoglobin identifies the type of hemoglobin?

A) Tetrameric molecule
B) Globin chain
C) Heme group
D) Salt bond

Question 20

Which of the following sets of values represents a normal adult hemoglobin distribution?

A) 90% A, 5% A₂, 5% F
B) 90% A, 8% A₂, 2% F
C) 97% A, 1% F, 2% A₂
D) 96% A, 2% A₂, 4% F

Question 21

What two molecules condense to begin heme synthesis?

A) Iron and protoporphyrin IX
B) Ferrochelatase and ALA dehydrase
C) Succinyl CoA and glycine
D) PBG deaminase and ALA dehydrase

Question 22

Produce an oxygen dissociation curve that would reflect the following conditions and give an example of a condition that would cause these shifts.
a. A shift to the left
b. A shift to the right

Question 23

Which abnormal hemoglobin contains a molecule of carbon monoxide?

A) Carboxyhemoglobin
B) Methemoglobin
C) Sulfhemoglobin
D) Deoxyhemoglobin

Question 24

Endothelium-derived relaxing factor has the ability to relax smooth muscle, dilate blood vessels, and:

A) Increase oxygen affinity
B) Decrease oxygenation of tissues
C) Inhibit of platelet aggregation
D) Decrease formation of methemoglobin

Question 25

How is oxygen transport affected in a patient with a defect in beta globin chain production? A patient with a defect in alpha chain production?

Question 26

Which of the following is detected using the Schumm's Test?

A) Sulfhemoglobin
B) Methemoglobin
C) Methemalbumin
D) Carboxyhemoglobin

Question 27

An anemic patient has increased serum bilirubin. Which of the following laboratory test results would indicate intravascular hemolysis in a patient?

A) Increased methemalbumin
B) Increased haptoglobin
C) Decreased hemopexin-heme complex
D) Decreased α - β dimers

Question 28

Which of the following abnormal hemoglobins is formed when iron is in the ferric state?

A) Oxyhemoglobin
B) Carboxyhemoglobin
C) Methemoglobin
D) Sulfhemoglobin

Question 29

Correlate embryonic/fetal hemoglobin production to stages of fetal hematopoiesis.

Question 30

What conditions can be caused by acquired nonfunctional hemoglobins?

A) Hypoxia and iron in ferric state
B) Sulfhemoglobin production
C) Hypoxia and cyanosis
D) Decrease in deoxyhemoglobin

Question 31

How would a tense configuration of hemoglobin impact the transport of oxygen? Explain your answer.

Question 32

Choose the hemoglobin that has the highest oxygen affinity.

A) Hb A
B) Hb F
C) Methemoglobin
D) Sulfhemoglobin

Question 33

What are normal values for forms of hemoglobin found in an infant under the age of 1 year? Over the age of 1? If they are the same, why? If they are different, why?

Question 34

How can you detect methemoglobin in the laboratory?

A) By spectral analysis at 541 nm
B) By spectral analysis at 630 nm
C) By hemoglobin quantitation using acid elution techniques
D) By looking at the patient's blood color-it will be blue

Question 35

When blood leaves the lungs and reaches the tissues, the PO₂ decreases and the P₅₀ level of O₂ will:

A) Decrease
B) Increase
C) Equilibrate to the PCO₂ level
D) Not change

Question 36

Which of the following is a control for hemoglobin synthesis?

A) Bohr effect
B) Cyanosis
C) Oxygen affinity
D) Activity of the heme enzyme (ALAS)

Question 37

Which of the following is not a breakdown product of hemoglobin:

A) Globin
B) Iron
C) Haptoglobin
D) Biliverdin

Question 38

Oxyhemoglobin is in the ________ configuration. This is achieved by the ________ of 2, 3-BPG.

A) Tense; presence
B) Tense; absence
C) Relaxed; presence
D) Relaxed; absence

Question 39

What element is central to all the structures of a hemoglobin molecule?

A) Nitrogen
B) Iron
C) Water
D) Oxygen

Question 40

Which of the following causes a left shift in the oxygen dissociation curve (normal blood pH: 7.35-7.45)?

A) A blood pH of 7.54
B) A body temperature of 103°F
C) An increased 2, 3-BPG concentration
D) An increased pCO₂