BICH 410 MULTIPLE CHOICE EXAM
QUESTIONS WITH CORRECT
ANSWERS
Which of the following IS NOT a characteristics of a functional protein's structure?
a) achieved by breaking and reforming covalent bonds
b) the three dimensional conformation of the protein
c) achieved by rotations about each single bond along the peptide backbone
d) the result amino acid side chain interactions
e) none of the above; all are true - Answer- a) achieved by breaking and reforming
covalent bonds
Which of the following statements about globular proteins is FALSE?
a) can display either open or closed symmetry
b) lock into rigid structure, once folding is complete
c) stability of quaternary structure is mostly due to burial of non polar side chains
d) secondary structural elements pack in layers
e) the 3D structure is only marginally stable - Answer- b) lock into rigid structure, once
folding is complete
Myoglobin is an example of a(n):
a) enzyme
b) regulatory
c) transport protein
d) structural protein
e) storage proteins - Answer- e) storage proteins
While the binding of O2 to myoglobin as a function of pO2 is described by a simple
_______ curve, the binding to hemoglobin is described by a more complex______
curve
a) sigmoidal; hyperbolic
b) exponential; hyperbolic
c) hyperbolic; sigmoidal
d) sigmoidal; bell shaped
e) hyperbolic; concave - Answer- c) hyperbolic; sigmoidal
,In sickle cell anemia, a hydrophobic amino acid replaces ______ on the beta subunit of
hemoglobin
a) tyrosine
b) glutamate
c) lysine
d) valine
e) glycine - Answer- b) glutamate
The change from deoxy- (T) to oxy - (R) hemoglobin
a) occurs in each protein subunit independently, when each heme binds oxygen
b) requires the binding of all four oxygen molecules, before any change happens
c) involves the movement of the heme Fe 2+ into the heme plane
d) results from His F8 being pulled toward the heme plane upon oxygen binding
e) both C and D - Answer- e) both C and D
Regarding hemoglobin, the Bohr effect refers to
a) the decrease in affinity for O2 when the pH goes up
b) the decrease in affinity for O2 when the pH goes down
c) the increase in the affinity for O2 when the O2 concentration goes up
d) the decrease in affinity for O2, when the BPG concentration goes up
e) the decrease in affinity for O2 when the BPG concentration goes down - Answer- b)
the decrease in affinity for O2 when the pH goes down
Which one of the following has the cellular components arranged in order of increasing
size?
a) amino acid < protein < mitochondrion < ribosome
b) amino acid < ribosome < protein < mitochondrion
c) amino acid < protein < ribosome < mitochondrion
d) protein < amino acid < mitochondrion < ribosome
e) protein < ribosome < mitochondrion < amino acid - Answer- c) amino acid < protein <
ribosome < mitochondrion
Living organisms:
a) are close systems
b) exist at equilibrium
c) exist outside the laws of thermodynamics
d) are open systems
e) are non of the above - Answer- d) are open systems
The second Law of thermodynamics states that the ______ of an isolated system
always increases
, a) entropy
b) enthalpy
c) free energy
d) chemical potential
e) none of the above - Answer- a) entropy
Consider the following metabolic reaction:
Succinyl-CoA + Acetoacetate -> Acetoacetyl-CoA +
Succinate Delta G not prime = 1.25 kJ/mol
What is the Key for this reaction at 25 degrees C?
a) 0.60
b) 1.66
c) 1.00
d) 422
e) 3.21 - Answer- a) 0.60
Consider the same metabolic reaction in the problem 4: the delta G not prime for the
hydrolysis of the Succinyl-CoA is -33.9 kJ/mol. Determine the delta G not prime for the
hydrolysis o fAcetoacetyle-CoA -> Acetoacetate + CoA
a) +32.7 kJ/mol
b) -32.7 kJ/mol
c) -35.2 kJ/mol
d) +35.2 kJ/mol
e) none of the above - Answer- c) -35.2 kJ/mol
A reaction with a positive delta H and a positive delta S is
a) enthalpically opposed, nut entropically favored
b) enthalpically favored, but entropically opposed
c) favorable at the temperatures higher than the ratio of the enthalpy to entropy
d)favorable at temperature below the ratio of enthalpy to entropy
e) A and C - Answer- e) A and C
An opposed process
a) occurs without the addition of free energy
b) is endergonic
c) has a delta G < 0
d) is all of the above
e) is none of the above - Answer- b) is endergonic
QUESTIONS WITH CORRECT
ANSWERS
Which of the following IS NOT a characteristics of a functional protein's structure?
a) achieved by breaking and reforming covalent bonds
b) the three dimensional conformation of the protein
c) achieved by rotations about each single bond along the peptide backbone
d) the result amino acid side chain interactions
e) none of the above; all are true - Answer- a) achieved by breaking and reforming
covalent bonds
Which of the following statements about globular proteins is FALSE?
a) can display either open or closed symmetry
b) lock into rigid structure, once folding is complete
c) stability of quaternary structure is mostly due to burial of non polar side chains
d) secondary structural elements pack in layers
e) the 3D structure is only marginally stable - Answer- b) lock into rigid structure, once
folding is complete
Myoglobin is an example of a(n):
a) enzyme
b) regulatory
c) transport protein
d) structural protein
e) storage proteins - Answer- e) storage proteins
While the binding of O2 to myoglobin as a function of pO2 is described by a simple
_______ curve, the binding to hemoglobin is described by a more complex______
curve
a) sigmoidal; hyperbolic
b) exponential; hyperbolic
c) hyperbolic; sigmoidal
d) sigmoidal; bell shaped
e) hyperbolic; concave - Answer- c) hyperbolic; sigmoidal
,In sickle cell anemia, a hydrophobic amino acid replaces ______ on the beta subunit of
hemoglobin
a) tyrosine
b) glutamate
c) lysine
d) valine
e) glycine - Answer- b) glutamate
The change from deoxy- (T) to oxy - (R) hemoglobin
a) occurs in each protein subunit independently, when each heme binds oxygen
b) requires the binding of all four oxygen molecules, before any change happens
c) involves the movement of the heme Fe 2+ into the heme plane
d) results from His F8 being pulled toward the heme plane upon oxygen binding
e) both C and D - Answer- e) both C and D
Regarding hemoglobin, the Bohr effect refers to
a) the decrease in affinity for O2 when the pH goes up
b) the decrease in affinity for O2 when the pH goes down
c) the increase in the affinity for O2 when the O2 concentration goes up
d) the decrease in affinity for O2, when the BPG concentration goes up
e) the decrease in affinity for O2 when the BPG concentration goes down - Answer- b)
the decrease in affinity for O2 when the pH goes down
Which one of the following has the cellular components arranged in order of increasing
size?
a) amino acid < protein < mitochondrion < ribosome
b) amino acid < ribosome < protein < mitochondrion
c) amino acid < protein < ribosome < mitochondrion
d) protein < amino acid < mitochondrion < ribosome
e) protein < ribosome < mitochondrion < amino acid - Answer- c) amino acid < protein <
ribosome < mitochondrion
Living organisms:
a) are close systems
b) exist at equilibrium
c) exist outside the laws of thermodynamics
d) are open systems
e) are non of the above - Answer- d) are open systems
The second Law of thermodynamics states that the ______ of an isolated system
always increases
, a) entropy
b) enthalpy
c) free energy
d) chemical potential
e) none of the above - Answer- a) entropy
Consider the following metabolic reaction:
Succinyl-CoA + Acetoacetate -> Acetoacetyl-CoA +
Succinate Delta G not prime = 1.25 kJ/mol
What is the Key for this reaction at 25 degrees C?
a) 0.60
b) 1.66
c) 1.00
d) 422
e) 3.21 - Answer- a) 0.60
Consider the same metabolic reaction in the problem 4: the delta G not prime for the
hydrolysis of the Succinyl-CoA is -33.9 kJ/mol. Determine the delta G not prime for the
hydrolysis o fAcetoacetyle-CoA -> Acetoacetate + CoA
a) +32.7 kJ/mol
b) -32.7 kJ/mol
c) -35.2 kJ/mol
d) +35.2 kJ/mol
e) none of the above - Answer- c) -35.2 kJ/mol
A reaction with a positive delta H and a positive delta S is
a) enthalpically opposed, nut entropically favored
b) enthalpically favored, but entropically opposed
c) favorable at the temperatures higher than the ratio of the enthalpy to entropy
d)favorable at temperature below the ratio of enthalpy to entropy
e) A and C - Answer- e) A and C
An opposed process
a) occurs without the addition of free energy
b) is endergonic
c) has a delta G < 0
d) is all of the above
e) is none of the above - Answer- b) is endergonic
