Deck 6: Hemoglobin

Question 1

Which of the following conditions will produce 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

Answer 1

High PO₂

Question 2

Oxygen affinity of hemoglobin is expressed by which of the following?

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

Answer 2

P50

Question 3

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

Answer 3

Stability and hemoglobin-oxygen affinity

Question 4

Choose the hemoglobin that has the highest oxygen affinity.

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

Question 5

The majority of carbon dioxide is transported in the body by:

A)Dissolving in plasma.
B)As carbonic acid.
C)Binding to hemoglobin.
D)Methemoglobin

Question 6

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

Question 7

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 8

What structure within hemoglobin identifies the type of hemoglobin?

A)Tetrameric molecule
B)Globin chains
C)Heme group
D)Salt bonds

Question 9

A shift to the left is caused by which of the following? (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

Question 10

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 11

Which of the following sets of values represents a normal 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 12

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 13

What does an elevated hemoglobin A1C indicate?

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 14

What are the chain designations for hemoglobin F?

A)α₂β₂
B)α₂δ₂
C)α₂γ₂
D)α₂ε₂

Question 15

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

A)ALAS2
B)PBG deaminase
C)Uroporphyrinogen III
D)Ferrochelatase

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)It cannot be determined based on the information given.

Question 17

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

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

Question 18

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

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

Question 19

In the complete hemoglobin structure, where is iron located?

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 20

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 21

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

Question 22

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 23

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

Question 24

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 25

In a hemoglobin molecule, what element is central to all the structures?

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

Question 26

What conditions may 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 27

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

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

Question 28

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 29

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 are they the same? If they are different, why are they different?

Question 30

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 31

Which abnormal hemoglobin has 200x more affinity for oxygen than does normal hemoglobin?

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

Question 32

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 33

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

Question 34

Which of the following blood vessels has the highest concentration of pO₂?

A)Pulmonary arteries
B)Pulmonary veins
C)Capillary beds
D)Veins

Question 35

Oxyhemoglobin is in the _______ configuration.This is achieved by the _______ of 2, 3 DPG.

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