A 100 mm hg 98 b 40 mm hg 75 c 80 mm hg 90 d 25 mm hg

A) 100 mm Hg : 98%
B) 40 mm Hg : 75%
C) 80 mm Hg : 90%
D) 25 mm Hg : 50%
E) 60 mm Hg : 80%
Answer: B
10

56) Which statement best describes why oxygen is unloaded in tissue that is highly active?
A) As temperature increases due to increased metabolism, the affinity of hemoglobin for oxygen is
decreased.
B) As temperature increases, the carbamino effect causes hemoglobin to release oxygen.
C) As temperature increases, the Bohr effect causes hemoglobin to release oxygen.
D) Highly active tissues produce more carbon dioxide, which competes for the heme groups in
hemoglobin, thereby displacing oxygen.
E) As temperature increases, the affinity for oxygen to hemoglobin increases, allowing more oxygen to be
carried to the tissues.
Answer: A
57) Which statement best describes the Bohr effect?
A) The Bohr effect speeds up metabolism and therefore increases the temperature in the body releasing
oxygen to the tissues.
B) The Bohr effect refers to a decrease in pH which decreases the affinity of hemoglobin for oxygen.
C) The Bohr effect refers to the cascading events that must take place in order to chemically remove
oxygen from hemoglobin.
D) The Bohr effect refers to the release of a chemical 2,3 BPG from erythrocytes that degrades hemoglobin
and releases oxygen.
E) The Bohr effect refers to a decrease in carbon dioxide concentration which decreases the affinity of
hemoglobin for oxygen.
Answer: B
58) The carbamino effect describes a change in the conformation of hemoglobin that is induced by a(n)
A) decrease in temperature.
B) increase in pH.
C) decrease in pH.
D) increase in CO
2
.
E) increase in temperature.
Answer: D
59) Which of the following statements about 2,3 - BPG is FALSE?
A) 2,3 - BPG is produced by red blood cells.
B) 2,3 - BPG produces a rightward shift in the hemoglobin - oxygen dissociation curve.
C) 2,3 - BPG increases the affinity of hemoglobin for oxygen.
D) 2,3 - BPG is an intermediate of glycolysis.
E) 2,3 - BPG synthesis is inhibited by high levels of oxyhemoglobin.
Answer: C
60) Where in blood does the conversion of CO
2
to bicarbonate occur?
A) capillary endothelial cells
B) plasma
C) leukocytes
D) platelets
E) erythrocytes
Answer: E
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61) What is the primary mechanism of carbon dioxide transport in blood?
A) bound to hemoglobin
B) as bicarbonate dissolved in the red blood cells
C) as bicarbonate dissolved in the plasma
D) dissolved in the red blood cells
E) dissolved in the plasma
Answer: C
62) Which statement best describes how people die of carbon monoxide poisoning?
A) As the carbon dioxide content of blood increases, a phenomenon known as the Haldane effect converts
the excess carbon dioxide to carbon monoxide until it reaches toxic levels.
B) Carbon monoxide is toxic because it binds more readily to hemoglobin than oxygen, thereby
decreasing the oxygen carrying capacity of blood.
C) Carbon monoxide causes the carbamino effect where carbon dioxide is stripped of an oxygen,
producing carbon monoxide.