BIOL 600 EXAM 2, KU Fa22 EXAM
QUESTIONS AND CORRECT ANSWERS
cooperative - ANSWER the hallmark binding behavior of hemoglobin; allows
it to be a good oxygen carrier
myoglobin - ANSWER protein that stores oxygen in muscle cells, and displays
M-M kinetics
hemoglobin - ANSWER protein that carries oxygen, and is found in RBCs
sigmoidal - ANSWER the shape of the binding curve for hemoglobin
66 - ANSWER percent of bound oxygen that hemoglobin releases when
traveling from the lungs to tissues
globin fold - ANSWER the recurring structure of alpha helices linked by turns
seen in both myoglobin and hemoglobin
protoporphyrin - ANSWER the organic component of the heme group in
hemoglobin
2+ - ANSWER oxidation state of iron in heme group of deoxyhemoglobin
3+ - ANSWER oxidation state of iron in heme group of oxyhemoglobin
proximal histidine - ANSWER the residue occupying the fifth coordination site
to which iron can bind in hemoglobin and myoglobin
fifth coordination site - ANSWER in heme group, this site is occupied by an
imidazole ring of a histidine called the proximal histidine
,distal histidine - ANSWER A histidine residue located near the heme group in
myoglobin and hemoglobin that helps maintain the heme iron in the Fe2+
oxidation state and inhibits carbon monoxide binding. It is on the opposite side
of the heme from the proximal histidine.
diamagnetic - ANSWER magnetic property of oxyhemoglobin
paramagnetic - ANSWER magnetic property of deoxyhemoglobin
T state - ANSWER the state of deoxyhemoglobin
R state - ANSWER the state of oxyhemoglobin
both - ANSWER Which model of cooperative binding does hemoglobin fit
with: concerted or sequential?
2,3-BPG - ANSWER highly anionic allosteric regulator in red blood cells that
decreases hemoglobin's affinity for binding oxygen, allowing it to deliver more
oxygen to tissues
fetal hemoglobin - ANSWER this form of hemoglobin has a higher oxygen
binding affinity than normal hemoglobin and differs in the fact that it has 2
alpha and 2 gamma chains (in the gamma chain, His143 is swapped for a serine
residue)
histidine and lysine - ANSWER the amino acid residues in hemoglobin that
interact with 2,3-BPG's many negative charges (2)
heterotropic effector - ANSWER an allosteric regulator molecule that is
different from the substrate
Bohr effect - ANSWER the phenomenon in which increasing the concentration
of carbon dioxide reduces hemoglobin's affinity for oxygen (lower pH decreases
binding affinity)
decrease - ANSWER the oxygen binding affinity of hemoglobin will (increase,
decrease) as pH decreases
, His146 - ANSWER at high pH, this amino acid residue in a beta chain of
hemoglobin isn't protonated, so oxygen binding is favored
increase - ANSWER the oxygen binding affinity of hemoglobin will (increase,
decrease) as the concentration of CO2 decreases
salt bridge - ANSWER at low pH, this structure forms between a His and an
Asp residue in deoxyhemoglobin, stabilizing the T state therefore reducing its
oxygen binding affinity
carbamates - ANSWER amino terminal structures that stabilize the T state of
hemoglobin through salt bridge interactions due to reacting with CO2
14 - ANSWER what percent of CO2 and H+ transport in the blood is accounted
for by hemoglobin?
bicarbonate - ANSWER the form in which CO2 is most commonly found in the
blood
sickle-cell anemia - ANSWER A genetic disorder that causes abnormal
hemoglobin due to a Val being subbed for a Glu residue in the beta chains,
reducing the molecule's solubility.
thalassemia - ANSWER A genetic disorder in which hemoglobin suffers a loss
or a reduction of one of its chains.
CH2O - ANSWER the empirical formula for carbohydrates
aldose - ANSWER a carbohydrate in which the carbonyl group is an aldehyde
ketose - ANSWER a carbohydrate in which the carbonyl group is a ketone
epimer - ANSWER a type of diastereomer in which the two molecules differ at
only one chiral center
anomer - ANSWER a type of diastereomer in which the two molecules differ at
a chiral center formed upon ring closure
QUESTIONS AND CORRECT ANSWERS
cooperative - ANSWER the hallmark binding behavior of hemoglobin; allows
it to be a good oxygen carrier
myoglobin - ANSWER protein that stores oxygen in muscle cells, and displays
M-M kinetics
hemoglobin - ANSWER protein that carries oxygen, and is found in RBCs
sigmoidal - ANSWER the shape of the binding curve for hemoglobin
66 - ANSWER percent of bound oxygen that hemoglobin releases when
traveling from the lungs to tissues
globin fold - ANSWER the recurring structure of alpha helices linked by turns
seen in both myoglobin and hemoglobin
protoporphyrin - ANSWER the organic component of the heme group in
hemoglobin
2+ - ANSWER oxidation state of iron in heme group of deoxyhemoglobin
3+ - ANSWER oxidation state of iron in heme group of oxyhemoglobin
proximal histidine - ANSWER the residue occupying the fifth coordination site
to which iron can bind in hemoglobin and myoglobin
fifth coordination site - ANSWER in heme group, this site is occupied by an
imidazole ring of a histidine called the proximal histidine
,distal histidine - ANSWER A histidine residue located near the heme group in
myoglobin and hemoglobin that helps maintain the heme iron in the Fe2+
oxidation state and inhibits carbon monoxide binding. It is on the opposite side
of the heme from the proximal histidine.
diamagnetic - ANSWER magnetic property of oxyhemoglobin
paramagnetic - ANSWER magnetic property of deoxyhemoglobin
T state - ANSWER the state of deoxyhemoglobin
R state - ANSWER the state of oxyhemoglobin
both - ANSWER Which model of cooperative binding does hemoglobin fit
with: concerted or sequential?
2,3-BPG - ANSWER highly anionic allosteric regulator in red blood cells that
decreases hemoglobin's affinity for binding oxygen, allowing it to deliver more
oxygen to tissues
fetal hemoglobin - ANSWER this form of hemoglobin has a higher oxygen
binding affinity than normal hemoglobin and differs in the fact that it has 2
alpha and 2 gamma chains (in the gamma chain, His143 is swapped for a serine
residue)
histidine and lysine - ANSWER the amino acid residues in hemoglobin that
interact with 2,3-BPG's many negative charges (2)
heterotropic effector - ANSWER an allosteric regulator molecule that is
different from the substrate
Bohr effect - ANSWER the phenomenon in which increasing the concentration
of carbon dioxide reduces hemoglobin's affinity for oxygen (lower pH decreases
binding affinity)
decrease - ANSWER the oxygen binding affinity of hemoglobin will (increase,
decrease) as pH decreases
, His146 - ANSWER at high pH, this amino acid residue in a beta chain of
hemoglobin isn't protonated, so oxygen binding is favored
increase - ANSWER the oxygen binding affinity of hemoglobin will (increase,
decrease) as the concentration of CO2 decreases
salt bridge - ANSWER at low pH, this structure forms between a His and an
Asp residue in deoxyhemoglobin, stabilizing the T state therefore reducing its
oxygen binding affinity
carbamates - ANSWER amino terminal structures that stabilize the T state of
hemoglobin through salt bridge interactions due to reacting with CO2
14 - ANSWER what percent of CO2 and H+ transport in the blood is accounted
for by hemoglobin?
bicarbonate - ANSWER the form in which CO2 is most commonly found in the
blood
sickle-cell anemia - ANSWER A genetic disorder that causes abnormal
hemoglobin due to a Val being subbed for a Glu residue in the beta chains,
reducing the molecule's solubility.
thalassemia - ANSWER A genetic disorder in which hemoglobin suffers a loss
or a reduction of one of its chains.
CH2O - ANSWER the empirical formula for carbohydrates
aldose - ANSWER a carbohydrate in which the carbonyl group is an aldehyde
ketose - ANSWER a carbohydrate in which the carbonyl group is a ketone
epimer - ANSWER a type of diastereomer in which the two molecules differ at
only one chiral center
anomer - ANSWER a type of diastereomer in which the two molecules differ at
a chiral center formed upon ring closure
