ch 5

1. Structural Proteins and Collagen

Question 1. _________ constitute the bulk of animal hair.

A) Tubulin dimers
B) Actin
C) Collagen
D) Myoglobin
E) Keratin filaments

Correct answer: E) Keratin filaments

Question 22. A plot of the binding of oxygen to myoglobin as a function of pO2 gives a _____ shape; a similar plot for hemoglobin gives a _____ shape.

A) Sigmoidal; sigmoidal
B) Hyperbolic; hyperbolic
C) Hyperbolic; sigmoidal
D) Sigmoidal; hyperbolic
E) Hyperbolic; exponential

Correct answer: C) Hyperbolic; sigmoidal

Question 89. Ascorbic acid is required for the production of _____ in collagen.

A) Hydroxyproline
B) Aspartate-semialdehyde
C) Desmosine
D) Hydroxylysine
E) Gamma-carboxyglutamic acid

Correct answer: A) Hydroxyproline

Question 90. Ascorbic acid is required for the production of _____ in collagen.

A) Hydroxyproline
B) Aspartate semialdehyde
C) Desmosine
D) Hydroxylysine
E) Gamma-carboxyglutamic acid

Correct answer: A) Hydroxyproline

Question 91. Ascorbic acid is required for the production of _____ in collagen.

A) Hydroxyproline
B) Gamma-carboxyglutamic acid
C) Aspartate-semialdehyde
D) Hydroxylysine
E) Desmosine

Correct answer: A) Hydroxyproline

Question 92. Ascorbic acid is required for the production of _____ in collagen.

A) Hydroxyproline
B) Aspartate-semialdehyde
C) Desmosine
D) Hydroxylysine
E) Gamma-carboxyglutamic acid

Correct answer: A) Hydroxyproline

Question 129. Bone and tendons contain _____ while hair and nails contain _____.

A) Tubulin; keratin
B) Actin; keratin
C) Collagen; actin
D) Tubulin; collagen
E) Collagen; keratin

Correct answer: E) Collagen; keratin

Question 130. Bone and tendons contain _____ while hair and nails contain _____.

A) Tubulin; keratin
B) Actin; keratin
C) Collagen; actin
D) Tubulin; collagen
E) Collagen; keratin

Correct answer: E) Collagen; keratin

Question 151. During the initial synthesis of collagen molecules, _____ and _____ are most often incorporated into the growing protein.

A) Ser; Pro
B) Ala; Gly
C) Gly; Pro
D) Ser; Gly
E) Pro; Ala

Correct answer: C) Gly; Pro

Question 307. The helical structure of collagen contains _____.

A) Three right-handed helices wound around each other in a right-handed triple helix
B) Three left-handed helices wound around each other in a left-handed triple helix
C) Three left-handed helices wound around each other in a right-handed triple helix
D) Three right-handed helices wound around each other in a left-handed triple helix
E) None of the rest

Correct answer: C) Three left-handed helices wound around each other in a right-handed triple helix

Question 308. The helical structure of collagen contains _____.

A) Three right-handed helices wound around each other in a right-handed triple helix
B) Three left-handed helices wound around each other in a left-handed triple helix
C) Three left-handed helices wound around each other in a right-handed triple helix
D) Three right-handed helices wound around each other in a left-handed triple helix
E) None of the rest

Correct answer: C) Three left-handed helices wound around each other in a right-handed triple helix

Question 450. Which amino acid is critical for crosslinking of collagen trimers?

A) Ser
B) Cys
C) His
D) Lys
E) Gln

Correct answer: D) Lys

Question 451. Which amino acid is critical for crosslinking of collagen trimers?

A) Ser
B) Cys
C) His
D) Lys
E) Gln

Correct answer: D) Lys

Question 452. Which amino acid is critical for crosslinking of keratin fibers?

A) Ser
B) Cys
C) His
D) Lys
E) Gln

Correct answer: B) Cys

Question 589. Which of the following statements does not apply to collagen?

A) The triple helical structure twists in the right-handed direction.
B) Cross-links between neighbouring hydroxylated Lys residues stabilize the helix.
C) Glycine at every third position is essential for the stability of the triple helical structure.
D) One single polypeptide forms a left-handed helix.
E) It contains hydroxylated amino acids.

Correct answer: B) Cross-links between neighbouring hydroxylated Lys residues stabilize the helix.

Question 590. Which of the following statements does not apply to collagen?

A) The triple helical structure twists in the right-handed direction.
B) Cross-links between neighbouring hydroxylated Lys residues stabilize the helix.
C) Glycine at every third position is essential for the stability of the triple helical structure.
D) One single polypeptide forms a left-handed helix.
E) It contains hydroxylated amino acids.

Correct answer: B) Cross-links between neighbouring hydroxylated Lys residues stabilize the helix.

Question 591. Which of the following statements does not apply to collagen?

A) The triple helical structure twists in the right-handed direction.
B) Cross-links between neighbouring Lys residues stabilize the helix.
C) Glycine at every third position is essential for the stability of the triple helical structure.
D) One single polypeptide forms a right-handed helix.
E) It contains hydroxylated amino acids.

Correct answer: D) One single polypeptide forms a right-handed helix.

Question 592. Which of the following statements does not apply to collagen?

A) The triple helical structure twists in the left-handed direction.
B) Cross-links between neighbouring Lys residues stabilize the helix.
C) Glycine at every third position is essential for the stability of the triple helical structure.
D) One single polypeptide forms a left-handed helix.
E) It contains hydroxylated amino acids.

Correct answer: A) The triple helical structure twists in the left-handed direction.

2. Cytoskeleton and Motor Proteins

Question 146. During the formation of microfilaments, which of the following occurs?

A) Polymerization proceeds slowly at first, then becomes more rapid once a longer polymer has formed
B) ATP binds to F-actin
C) ATP hydrolysis is catalyzed by G-actin
D) None of the rest
E) F-actin polymerizes, becoming G-actin

Correct answer: A) Polymerization proceeds slowly at first, then becomes more rapid once a longer polymer has formed

Question 147. During the formation of microfilaments, which of the following occurs?

A) Polymerization proceeds slowly at first, then becomes more rapid once a longer polymer has formed
B) ATP binds to F-actin
C) ATP hydrolysis is catalyzed by G-actin
D) None of the rest
E) F-actin polymerizes, becoming G-actin

Correct answer: A) Polymerization proceeds slowly at first, then becomes more rapid once a longer polymer has formed

Question 148. During the formation of microfilaments, which of the following occurs?

A) Polymerization proceeds slowly at first, then becomes more rapid once a longer polymer has formed
B) ATP binds to G-actin
C) ATP hydrolysis is catalyzed by F-actin
D) G-actin polymerizes, becoming F-actin
E) All of the rest

Correct answer: E) All of the rest

Question 149. During the formation of microfilaments, which of the following occurs?

A) Polymerization proceeds quickly at first, then slows after about ten actin monomers have polymerized
B) ATP binds to F-actin
C) ATP hydrolysis is catalyzed by F-actin
D) None of the rest
E) F-actin polymerizes, becoming G-actin

Correct answer: C) ATP hydrolysis is catalyzed by F-actin

Question 150. During the formation of microfilaments, which of the following occurs?

A) Polymerization proceeds slowly at first, then becomes more rapid once a longer polymer has formed
B) ATP binds to F-actin
C) ATP hydrolysis is catalyzed by G-actin
D) None of the rest
E) F-actin polymerizes, becoming G-actin

Correct answer: A) Polymerization proceeds slowly at first, then becomes more rapid once a longer polymer has formed

Question 153. Each kinesin head contains a binding site for _____ and a binding site for _____.

A) Tubulin; GTP
B) Actin; ATP
C) Another kinesin molecule; GTP
D) Tubulin; ATP
E) Myosin; ATP

Correct answer: D) Tubulin; ATP

Question 154. Each myosin head contains a binding site for _____ and a binding site for _____.

A) Tubulin; GTP
B) Actin; ATP
C) Another myosin molecule; ATP
D) None of the rest
E) Kinesin; GTP

Correct answer: B) Actin; ATP

Question 306. The heads of kinesin bind to _____; the light chains of kinesin bind to _____.

A) Tubulin; proteins in the membrane of a vesicle
B) Collagen fibers; proteins in the cell membrane
C) Proteins in the membrane of a vesicle; actin
D) Proteins in the membrane of an organelle; tubulin
E) None of the rest

Correct answer: A) Tubulin; proteins in the membrane of a vesicle

Question 396. What is the most prevalent secondary structure observed in the proteins of intermediate filaments?

A) Both alpha-helices and beta-helices are observed
B) Alpha-helices
C) Alpha-sheets
D) Beta-sheets
E) Beta-helices

Correct answer: B) Alpha-helices

Question 491. Which of the following details the nucleotide-binding site when tubulin dimers assemble into microtubules?

A) The alpha site is bound to GTP; the beta site is unoccupied following GTP hydrolysis and release of GDP
B) Both alpha and beta sites are bound to GDP
C) Both alpha and beta sites are bound to GTP
D) The alpha site is bound to GTP; the beta site is bound to GDP
E) The alpha site is bound to GDP; the beta site is bound to GTP

Correct answer: D) The alpha site is bound to GTP; the beta site is bound to GDP

Question 498. Which of the following fibers is correctly paired with the protein that forms the fiber?

A) Microtubule: tubulin
B) Extracellular support fibers: collagen
C) Intermediate filaments: keratin
D) Microfilaments: actin
E) All of the rest

Correct answer: E) All of the rest

Question 635. ____ forms microfilaments in cells.

A) Tubulin dimers
B) Actin
C) Collagen
D) Myoglobin

Correct answer: B) Actin

3. Myoglobin and Hemoglobin Structure

Question 188. Heme is considered a _____.

A) Prosthetic group
B) Catalyst
C) Coenzyme
D) None of these choices
E) Cofactor

Correct answer: A) Prosthetic group

Question 269. Myoglobin is _____; hemoglobin is _____.

A) Monomeric; trimeric
B) Dimeric; trimeric
C) Monomeric; dimeric
D) Monomeric; tetrameric
E) Dimeric; tetrameric

Correct answer: D) Monomeric; tetrameric

Question 296. The central ion of the heme group of hemoglobin is _____.

A) None of these choices
B) Cu(+)
C) Cu(2+)
D) Fe(3+)
E) Fe(2+)

Correct answer: E) Fe(2+)

Question 297. The central ion of the heme group of hemoglobin is _____.

A) None of these choices
B) Cu(+)
C) Cu(2+)
D) Fe(3+)
E) Fe(2+)

Correct answer: E) Fe(2+)

Question 298. The central ion of the heme group of methemoglobin is _____.

A) None of these choices
B) Cu(+)
C) Cu(2+)
D) Fe(3+)
E) Fe(2+)

Correct answer: D) Fe(3+)

Question 299. The central ion of the heme group of methemoglobin is _____.

A) None of the rest
B) Cu+
C) Cu2+
D) Fe3+
E) Fe2+

Correct answer: D) Fe3+

Question 300. The central ion of the heme group of metmyoglobin is _____.

A) None of the rest
B) Cu+
C) Cu2+
D) Fe3+
E) Fe2+

Correct answer: D) Fe3+

Question 402. What is the prominent type of secondary structure observed in myoglobin?

A) Parallel beta-sheets
B) Alpha-bends
C) Antiparallel beta-sheets
D) Beta-helices
E) Alpha-helices

Correct answer: E) Alpha-helices

Question 403. What is the prominent type of secondary structure observed in myoglobin?

A) Parallel beta-sheets
B) Alpha-bends
C) Antiparallel beta-sheets
D) Beta-helices
E) Alpha-helices

Correct answer: E) Alpha-helices

Question 404. What is the prominent type of secondary structure observed in myoglobin?

A) Parallel beta-sheets
B) Antiparallel beta-sheets
C) Coiled-coil
D) Left-handed triple helix
E) Alpha-helices

Correct answer: E) Alpha-helices

Question 445. When oxygen is bound to the heme group of myoglobin, it is coordinated between _____ and _____.

A) None of the rest
B) E7 His; Fe2+ of heme
C) E7 His; Fe3+ of heme
D) F8 His; Fe3+ of heme
E) F8 His; Fe2+ of heme

Correct answer: B) E7 His; Fe2+ of heme

Question 503. Which of the following individuals was/were the first to determine the crystal structure of myoglobin?

A) All of the listed individuals
B) James Watson
C) John Kendrew
D) Max Perutz
E) Linus Pauling

Correct answer: C) John Kendrew

4. Hemoglobin Oxygen Binding and Cooperativity

Question 189. Hemoglobin is 50% saturated with oxygen when pO2 = 26 torr. If hemoglobin exhibited hyperbolic binding (as myoglobin does) with 50% saturation at 26 torr, which of the following statements is correct? (pO2 = 100 in the lungs and pO2 = 30 in the tissues; fractional saturation YO2 = pO2 / and K = p50 = pO2 when YO2 = 0.5)

A) The fractional saturation when pO2 = 30 torr is 0.24
B) Hemoglobin can only use approximately 1/4 of its capacity to deliver O2 to the tissues
C) Hemoglobin is fully oxidized in the tissues
D) The fractional saturation when pO2 = 100 torr is 0.59
E) None of the rest

Correct answer: B) Hemoglobin can only use approximately 1/4 of its capacity to deliver O2 to the tissues

Question 309. The idea that binding of one molecule of oxygen to hemoglobin enhances further binding of oxygen to hemoglobin is called _____.

A) None of the rest
B) Allosterism
C) Cooperativity
D) Homologous binding
E) Fractional saturation

Correct answer: C) Cooperativity

Question 310. The idea that binding of one molecule of oxygen to hemoglobin enhances further binding of oxygen to hemoglobin is called _____.

A) None of the choices
B) Allosterism
C) Cooperativity
D) Homologous binding
E) Fractional saturation

Correct answer: C) Cooperativity

Question 311. The idea that binding of one molecule of oxygen to hemoglobin enhances further binding of oxygen to hemoglobin is called _____.

A) None of the rest
B) Allosterism
C) Cooperativity
D) Homologous binding
E) Fractional saturation

Correct answer: C) Cooperativity

Question 312. The idea that binding of one molecule of oxygen to hemoglobin enhances further binding of oxygen to hemoglobin is called _____.

A) None of the choices
B) Allosterism
C) Cooperativity
D) Homologous binding
E) Fractional saturation

Correct answer: C) Cooperativity

Question 313. The idea that binding of one molecule of oxygen to myoglobin enhances further binding of oxygen to myoglobin is called _____.

A) None of the choices
B) Allosterism
C) Cooperativity
D) Homologous binding
E) Fractional saturation

Correct answer: A) None of the choices

Question 314. The individual hemoglobin subunits and myoglobin share similar _____ structure but have rather different _____ structure.

A) Secondary; tertiary
B) Primary; secondary
C) Primary; tertiary
D) Secondary and tertiary; primary
E) Primary and secondary; tertiary

Correct answer: D) Secondary and tertiary; primary

Question 492. Which of the following explains the conversion of hemoglobin subunits from deoxy to oxy state?

A) None of the rest
B) All four subunits switch simultaneously
C) Both alpha subunits simultaneously switch first followed by both beta subunits
D) Each subunit switches only upon oxygen binding to the particular subunit
E) Both beta subunits simultaneously switch first followed by both alpha subunits

Correct answer: B) All four subunits switch simultaneously

Question 557. Which of the following occurs in hemoglobin upon oxygen binding?

A) The heme Fe2+ is pulled out of the plane of the heme group
B) Hemoglobin changes from the R state to the T state
C) The His coordinated to the heme Fe2+ is pushed away from the heme group
D) The central cavity between the four subunits is decreased in size
E) All of the rest occur

Correct answer: D) The central cavity between the four subunits is decreased in size

Question 558. Which of the following occurs in hemoglobin upon oxygen binding?

A) The heme Fe2+ is pushed away from the plane of the heme group
B) Hemoglobin changes from the R state to the T state
C) The His coordinated to the heme Fe2+ is pulled towards the heme group
D) The central cavity between the four subunits is increased in size
E) All of the rest occur

Correct answer: C) The His coordinated to the heme Fe2+ is pulled towards the heme group

Question 559. Which of the following occurs in hemoglobin upon oxygen binding?

A) The heme Fe2+ is pulled out of the plane of the heme group
B) Hemoglobin changes from the R state to the T state
C) The His coordinated to the heme Fe2+ is pushed away from the heme group
D) The central cavity between the four subunits is decreased in size
E) All of the rest occur

Correct answer: D) The central cavity between the four subunits is decreased in size

Question 560. Which of the following occurs in hemoglobin upon oxygen binding?

A) The heme Fe2+ is pushed away from the plane of the heme group
B) Hemoglobin changes from the T state to the R state
C) The Arg coordinated to the heme Fe2+ is pulled towards the heme group
D) The central cavity between the four subunits is increased in size
E) All of the rest occur

Correct answer: B) Hemoglobin changes from the T state to the R state

Question 561. Which of the following occurs in hemoglobin upon oxygen binding?

A) The heme Fe2+ is pulled out of the plane of the heme group
B) Hemoglobin changes from the R state to the T state
C) The His coordinated to the heme Fe2+ is pushed away from the heme group
D) The central cavity between the four subunits is decreased in size
E) All of the rest occur

Correct answer: D) The central cavity between the four subunits is decreased in size

Question 562. Which of the following occurs in hemoglobin upon oxygen binding?

A) The heme Fe2+ is pulled towards the plane of the heme group
B) Hemoglobin changes from the T state to the R state
C) The His coordinated to the heme Fe2+ is pulled towards the heme group
D) The central cavity between the four subunits is decreased in size
E) All of the rest occur

Correct answer: E) All of the rest occur

Question 563. Which of the following occurs in hemoglobin upon oxygen binding?

A) The heme Fe2+ is pulled out of the plane of the heme group
B) Hemoglobin changes from the R state to the T state
C) The His coordinated to the heme Fe2+ is pushed away from the heme group
D) The central cavity between the four subunits is decreased in size
E) All of the rest occur

Correct answer: D) The central cavity between the four subunits is decreased in size

Question 564. Which of the following occurs in hemoglobin upon oxygen binding?

A) The heme Fe2+ is pulled out of the plane of the heme group
B) Hemoglobin changes from the R state to the T state
C) The His coordinated to the heme Fe2+ is pushed away from the heme group
D) The central cavity between the four subunits is decreased in size
E) All of the rest occur

Correct answer: D) The central cavity between the four subunits is decreased in size

Question 565. Which of the following occurs in hemoglobin upon oxygen binding?

A) The heme Fe2+ is pushed away from the plane of the heme group
B) Hemoglobin changes from the T state to the R state
C) The Arg coordinated to the heme Fe2+ is pulled towards the heme group
D) The central cavity between the four subunits is increased in size
E) All of the rest occur

Correct answer: B) Hemoglobin changes from the T state to the R state

Question 566. Which of the following occurs in hemoglobin upon oxygen binding?

A) The heme Fe2+ is pulled into the plane of the heme group
B) Hemoglobin changes from the T state to the R state
C) The His coordinated to the heme Fe2+ is pulled towards the heme group
D) The central cavity between the four subunits is increased in size
E) All of the rest occur

Correct answer: A, B and C

Question 567. Which of the following occurs in hemoglobin upon oxygen binding?

A) The heme Fe2+ is pulled into the plane of the heme group
B) Hemoglobin changes from the T state to the R state
C) The His coordinated to the heme Fe2+ is pulled towards the heme group
D) The central cavity between the four subunits is decreased in size
E) All of the rest occur

Correct answer: E) All of the rest occur

5. Hemoglobin Regulation and Carbon Dioxide

Question 195. How does CO2 affect hemoglobin-oxygen binding?

A) None of the rest
B) CO2 binds directly to the oxygen binding site, displacing oxygen and thus promoting the deoxy state
C) CO2 displaces BPG, thus promoting the oxy state
D) CO2 is converted to bicarbonate and H+ which promotes the oxy state
E) CO2 is converted to bicarbonate and H+ which promotes the deoxy state

Correct answer: E) CO2 is converted to bicarbonate and H+ which promotes the deoxy state

Question 196. How does CO2 affect hemoglobin-oxygen binding?

A) None of the rest
B) CO2 binds directly to the oxygen binding site, displacing oxygen and thus promoting the deoxy state
C) CO2 displaces BPG, thus promoting the oxy state
D) CO2 is converted to bicarbonate and H+ which promotes the oxy state
E) CO2 is converted to bicarbonate and H+ which promotes the deoxy state

Correct answer: E) CO2 is converted to bicarbonate and H+ which promotes the deoxy state

Question 197. How does CO2 affect hemoglobin-oxygen binding?

A) None of the rest
B) CO2 binds directly to the oxygen binding site, displacing oxygen and thus promoting the deoxy state
C) CO2 displaces BPG, thus promoting the oxy state
D) The presence of CO2 lowers the pH of the solution which promotes the deoxy state
E) CO2 is converted to bicarbonate and H+ which promotes the oxy state

Correct answer: D) The presence of CO2 lowers the pH of the solution which promotes the deoxy state

Question 198. How does CO2 affect hemoglobin-oxygen binding?

A) None of the rest
B) CO2 binds directly to the oxygen binding site, displacing oxygen and thus promoting the deoxy state
C) CO2 displaces BPG, thus promoting the oxy state
D) CO2 is converted to bicarbonate and H+ which promotes the oxy state
E) CO2 is converted to bicarbonate and H+ which promotes the deoxy state

Correct answer: E) CO2 is converted to bicarbonate and H+ which promotes the deoxy state

Question 449. Which allosteric effector has the greatest ability to stabilize the deoxy state of hemoglobin?

A) All of the rest have equal ability
B) BPG
C) CO2
D) O2
E) H+

Correct answer: B) BPG

Question 600. Which of the following statements is not true about carbonic anhydrase?

A) It is particularly abundant in red blood cells
B) It catalyzes the conversion of bicarbonate to CO2 in the lung
C) It catalyzes the conversion of dissolved CO2 to bicarbonate in the tissue
D) It is not found in plant tissues
E) It is found in all animals

Correct answer: D) It is not found in plant tissues

Question 601. Which of the following statements is true about carbonic anhydrase?

A) It is particularly abundant in red blood cells
B) It catalyzes the conversion of bicarbonate to CO2 in the lung
C) It catalyzes the conversion of dissolved CO2 to bicarbonate in the tissue
D) It is found in most tissues
E) All of the rest are correct

Correct answer: E) All of the rest are correct

Question 626. Why is the decreased affinity of fetal hemoglobin for BPG advantageous to the fetus?

A) With fewer BPG molecules bound there are more heme residues available for O2 binding
B) BPG is available to bind to fetal myoglobin, helping to release O2 in fetal muscle tissue
C) Decreased BPG binding biases the fetal hemoglobin toward the T state
D) More free BPG is available to bind to adult hemoglobin, resulting in a shift of adult hemoglobin to the R state
E) It reduces fetal hemoglobin's P50

Correct answer: E) It reduces fetal hemoglobin's P50

Question 627. With respect to oxygen saturation, hemoglobin is _____ saturated at the pO2 of the lungs and _____ saturated at the pO2 of the tissue.

A) Greater than 90%; between 30 and 70%
B) 20%; 20%
C) 25%; 20%
D) 50%; between 30 and 70%
E) 50%; 20%

Correct answer: A) Greater than 90%; between 30 and 70%

6. Sickle Cell Hemoglobin

Question 239. In Hb S, a ___ residue is replaced by a ___ residue.

A) Glycine; valine
B) Aspartate; lysine
C) Glutamate; histidine
D) Glycine; isoleucine
E) Glutamate; valine

Correct answer: E) Glutamate; valine

Question 240. In Hb S, a ___ residue is replaced by a ___ residue.

A) None of the rest
B) Aspartate; lysine
C) Glutamate; histidine
D) Glycine; valine
E) Glycine; isoleucine

Correct answer: A) None of the rest

Question 241. In Hb S, a valine residue binds to a(n) ___ patch causing ___ of the hemoglobin.

A) None of the rest
B) Acidic; unfolding
C) Basic; aggregation
D) Hydrophobic; aggregation
E) Hydrophilic; unfolding

Correct answer: D) Hydrophobic; aggregation

Question 292. The aggregation of Hb S occurs in the ___ state, thus the formation of aggregates is likely to occur at ___.

A) Oxy; high altitude
B) Deoxy; Hawaiian beaches
C) Deoxy; high altitude
D) Oxy; Hawaiian beaches
E) None of the rest

Correct answer: C) Deoxy; high altitude

Question 293. The aggregation of Hb S occurs in the ___ state, thus the formation of aggregates is most likely to occur in the ___.

A) Oxy; capillaries
B) Deoxy; arteries
C) Deoxy; capillaries
D) Oxy; arteries
E) None of the rest

Correct answer: C) Deoxy; capillaries

7. Carbon Monoxide

Question 475. Which of the following best explains the ability for carbon monoxide (CO) to bind to hemoglobin (Hb) despite the relatively low concentrations of CO?

A) None of the choices
B) CO binds to Hb about 250 times more strongly than oxygen
C) CO binds to Hb about 5 times more strongly than oxygen
D) CO binds to Hb with less affinity than oxygen
E) CO binds to Hb with an affinity about the same as oxygen

Correct answer: B) CO binds to Hb about 250 times more strongly than oxygen

Question 476. Which of the following best explains the ability for carbon monoxide (CO) to bind to hemoglobin (Hb) despite the relatively low concentrations of CO?

A) None of the choices
B) CO binds to Hb about 250 times more strongly than oxygen
C) CO binds to Hb about 5 times more strongly than oxygen
D) CO binds to Hb with less affinity than oxygen
E) CO binds to Hb with an affinity about the same as oxygen

Correct answer: B) CO binds to Hb about 250 times more strongly than oxygen

Question 477. Which of the following best explains the ability for carbon monoxide (CO) to bind to hemoglobin (Hb) despite the relatively low concentrations of CO?

A) None of the choices
B) CO binds to Hb about 250 times more strongly than oxygen
C) CO binds to Hb about 5 times more strongly than oxygen
D) CO binds to Hb with less affinity than oxygen
E) CO binds to Hb with an affinity about the same as oxygen

Correct answer: B) CO binds to Hb about 250 times more strongly than oxygen

8. Nobel Prizes and Historical Discoveries

Question 290. The Nobel prize was/were awarded to which of the following individuals?

A) All of the listed individuals
B) James Watson
C) John Kendrew
D) Max Perutz
E) Linus Pauling

Correct answer: A) All of the listed individuals