BCH4024 EXAM 1 COMBINED SET
QUESTIONS WITH 100% CORRECT
ANSWERS
The structure of myoglobin and hemoglobin are very ---------, suggesting that they come
from a common ancestor and conservation of protein folding - Answer-similar
Hemoglobin is fully saturated at lung O2 pressure, ------ of the O2 are dumped to the
peripheral tissues. 1/3 returns to lungs - Answer-2/3
--------means that hemoglobin subunit interactions have altered O2 saturation curve -
Answer-Cooperativity
Binding curve in the standard suggests that the binding gets --------from the 1st to 3rd
site - Answer-stronger
The O2 in our lungs and the O2 in the atmosphere would be equal if not for high ----------
-- and -------- - Answer-vapor pressure, CO2
John Dalton proved that the concentration of dissolved gas is always --------proportional
to the -------of the gas in equilibrium with the liquid, which is why we use pO2 - Answer-
directly, pressure
---------buffers O2 concentrations in muscle - Answer-Myoglobin
O2 saturation curve for myoglobin is ------------. It has a high affinity for hemoglobin O2 -
Answer-hyperbolic
Higher activity levels lowers the - Answer-pO2
When you treat hemoglobin with ------------, it breaks the tetramer by binding to -------, so
there is no cooperativity and O2 is dumped to tissues - Answer-hgCl2, cysteine
Myoglobin O2 binding curve is ------(--------- midpoint) than hemoglobin with a -------
curve - Answer-hyperbolic, lower, sigmoidal
Monod-Wyman-Changeux or the --------------cooperativity model of O2 binding to
hemoglobin gives two conformational state, ------ and ------------ (no hybrid forms) -
Answer-concerted, T (tense), R (relaxed)
,The T state of the concerted cooperativity model has 4 ---------- attached to each other.
The R state has 4 -------attached to each other - Answer-squares, circles
The transition from R to T is ----------- - Answer-all or none
T state of the concerted cooperativity model has -----------affinity for O2, which is why it
is favored when no O2 is bound - Answer-no
R state of concerted cooperativity has ------------affinity for O2, O2 binding favors it -
Answer-moderate
O2 binds to the --------in the R state because it shifts away from the -------- - Answer-
iron, hisitidine
In the T state of the concerted cooperativity model, ---------is bound to -------so there is
no bind of O2 - Answer-histidine, iron
When we go from the T to R state, there is no change in ------------ - Answer-volume
The T state is more stable than the -------R state (R0) - Answer-initial
The degree of saturation of R matches the stability of the T, this is known as the ----------
point - Answer-tipping
In the regular hemoglobin sigmoidal curve, the tipping point is the ------------ of the entire
curve - Answer-midpoint
At the ---------point, half of the protein is in R state and the other half in T state - Answer-
tipping
In the sequential binding of cooperativity, there are three types - Answer-negative,
positive and no cooperativity
Which state in the concerted cooperativity is more stable - Answer-T
In the concerted model of cooperativity, the energy change of states R1, R2, R3, R4 is
the same on each transition so the --------is constant, but stability is increasing until R4 -
Answer-K
The lag in the sigmoidal curve of the hemoglobin saturation has to do with the transition
from the T to R state, which is -----------. The elongation state follows where O2 is
binding favorably to the subunits - Answer-unfavorable
In the sequential module, when there is no cooperativity, the delta G's are ----------- and
the midpoint is ---------- - Answer-equal, lowest
, In the sequential model, when there is + cooperativity, the delta G1 is ---------than the
delta G2 and the midpoint is a bit -------------than when there is no cooperativity and
K1>K2 - Answer-less, higher
In + sequential cooperativity, there is tighter bonding as a result of the presence of -------
- - Answer-CO
In the ------- sequential cooperativity, the bonding is ----------tight, the midpoint is highest
and delta G1 is ----than delta G2, K1 and K2 are different from each other K2 higher -
Answer-negative, less, greater
So, basically, it turns out that the sequential model does not apply to --------- - Answer-
hemoglobin
CO just binds --------than O2, so when you have CO poisoning O2 doesnt get released
to tissues - Answer-tighter
The pO2 in the lungs and supply to tissues just drops with more CO until our graph
looks --------. To begin with no CO, the graph is sigmoidal - Answer-hyperbolic
Only the ----------or concerted model can describe the effects of CO in a graph,
sequential model cannot - Answer-Monod
In the concerted model, when only CO is binding, we have transitions from R1-R2-R3-
R4 change in K's and delta G's that are ---------. - Answer-the same
When we have 1/4 of the tetramers filled with CO, the other 3/4 go on with --------, so we
get pO2 that is 75%, but this is -------observed, this is why the hemoglobin ------follow
the sequential model - Answer-cooperativity, never, does not
When we have 1/4 of the tetramers filled with CO, the first change in G from R0-R1 is ---
-------than the ones that follower, which are all the same (change). REMEMBER, this is
not observed because hemoglobin follows ONLY the concerted model - Answer-larger
At higher elevations, we have reduced O2, lactic acid lowers blood PH. This trigger ------
------ synthesis by RBC - Answer-2,3 BPG
The 2,3 BPG ---------deoxy hemoglobin, favoring ---------dissociation and eventual
release to tissues, this is restored when you return down to normal conditions - Answer-
stabilizes, O2
2,3 BPG binds to the hole in the ----------state, making it more ------, which means harder
to get O2 to -------and easier to release - Answer-T, stable, bind
Hemoglobin releases --------O2 at low Ph - Answer-more
QUESTIONS WITH 100% CORRECT
ANSWERS
The structure of myoglobin and hemoglobin are very ---------, suggesting that they come
from a common ancestor and conservation of protein folding - Answer-similar
Hemoglobin is fully saturated at lung O2 pressure, ------ of the O2 are dumped to the
peripheral tissues. 1/3 returns to lungs - Answer-2/3
--------means that hemoglobin subunit interactions have altered O2 saturation curve -
Answer-Cooperativity
Binding curve in the standard suggests that the binding gets --------from the 1st to 3rd
site - Answer-stronger
The O2 in our lungs and the O2 in the atmosphere would be equal if not for high ----------
-- and -------- - Answer-vapor pressure, CO2
John Dalton proved that the concentration of dissolved gas is always --------proportional
to the -------of the gas in equilibrium with the liquid, which is why we use pO2 - Answer-
directly, pressure
---------buffers O2 concentrations in muscle - Answer-Myoglobin
O2 saturation curve for myoglobin is ------------. It has a high affinity for hemoglobin O2 -
Answer-hyperbolic
Higher activity levels lowers the - Answer-pO2
When you treat hemoglobin with ------------, it breaks the tetramer by binding to -------, so
there is no cooperativity and O2 is dumped to tissues - Answer-hgCl2, cysteine
Myoglobin O2 binding curve is ------(--------- midpoint) than hemoglobin with a -------
curve - Answer-hyperbolic, lower, sigmoidal
Monod-Wyman-Changeux or the --------------cooperativity model of O2 binding to
hemoglobin gives two conformational state, ------ and ------------ (no hybrid forms) -
Answer-concerted, T (tense), R (relaxed)
,The T state of the concerted cooperativity model has 4 ---------- attached to each other.
The R state has 4 -------attached to each other - Answer-squares, circles
The transition from R to T is ----------- - Answer-all or none
T state of the concerted cooperativity model has -----------affinity for O2, which is why it
is favored when no O2 is bound - Answer-no
R state of concerted cooperativity has ------------affinity for O2, O2 binding favors it -
Answer-moderate
O2 binds to the --------in the R state because it shifts away from the -------- - Answer-
iron, hisitidine
In the T state of the concerted cooperativity model, ---------is bound to -------so there is
no bind of O2 - Answer-histidine, iron
When we go from the T to R state, there is no change in ------------ - Answer-volume
The T state is more stable than the -------R state (R0) - Answer-initial
The degree of saturation of R matches the stability of the T, this is known as the ----------
point - Answer-tipping
In the regular hemoglobin sigmoidal curve, the tipping point is the ------------ of the entire
curve - Answer-midpoint
At the ---------point, half of the protein is in R state and the other half in T state - Answer-
tipping
In the sequential binding of cooperativity, there are three types - Answer-negative,
positive and no cooperativity
Which state in the concerted cooperativity is more stable - Answer-T
In the concerted model of cooperativity, the energy change of states R1, R2, R3, R4 is
the same on each transition so the --------is constant, but stability is increasing until R4 -
Answer-K
The lag in the sigmoidal curve of the hemoglobin saturation has to do with the transition
from the T to R state, which is -----------. The elongation state follows where O2 is
binding favorably to the subunits - Answer-unfavorable
In the sequential module, when there is no cooperativity, the delta G's are ----------- and
the midpoint is ---------- - Answer-equal, lowest
, In the sequential model, when there is + cooperativity, the delta G1 is ---------than the
delta G2 and the midpoint is a bit -------------than when there is no cooperativity and
K1>K2 - Answer-less, higher
In + sequential cooperativity, there is tighter bonding as a result of the presence of -------
- - Answer-CO
In the ------- sequential cooperativity, the bonding is ----------tight, the midpoint is highest
and delta G1 is ----than delta G2, K1 and K2 are different from each other K2 higher -
Answer-negative, less, greater
So, basically, it turns out that the sequential model does not apply to --------- - Answer-
hemoglobin
CO just binds --------than O2, so when you have CO poisoning O2 doesnt get released
to tissues - Answer-tighter
The pO2 in the lungs and supply to tissues just drops with more CO until our graph
looks --------. To begin with no CO, the graph is sigmoidal - Answer-hyperbolic
Only the ----------or concerted model can describe the effects of CO in a graph,
sequential model cannot - Answer-Monod
In the concerted model, when only CO is binding, we have transitions from R1-R2-R3-
R4 change in K's and delta G's that are ---------. - Answer-the same
When we have 1/4 of the tetramers filled with CO, the other 3/4 go on with --------, so we
get pO2 that is 75%, but this is -------observed, this is why the hemoglobin ------follow
the sequential model - Answer-cooperativity, never, does not
When we have 1/4 of the tetramers filled with CO, the first change in G from R0-R1 is ---
-------than the ones that follower, which are all the same (change). REMEMBER, this is
not observed because hemoglobin follows ONLY the concerted model - Answer-larger
At higher elevations, we have reduced O2, lactic acid lowers blood PH. This trigger ------
------ synthesis by RBC - Answer-2,3 BPG
The 2,3 BPG ---------deoxy hemoglobin, favoring ---------dissociation and eventual
release to tissues, this is restored when you return down to normal conditions - Answer-
stabilizes, O2
2,3 BPG binds to the hole in the ----------state, making it more ------, which means harder
to get O2 to -------and easier to release - Answer-T, stable, bind
Hemoglobin releases --------O2 at low Ph - Answer-more
