BIOCHEM 384 EXAM 2 Question and
answers correctly solved 2025/2026
Which separation technique exploits the density differences of biomolecules and organelles? - correct
answer ✔Centrifugation using centrifuge tubes in a rotor placed in a centrifuge.
What protein feature will cause the protein to bind to a metal in chelation affinity
chromatography—specifically, a resin with immobilized Ni2+? - correct answer ✔Recombinant proteins
engineered to have six histidines at the N or C terminus of the protein.
Sodium dodecylsulfate (SDS) plays an important role in SDS PAGE. Select the correct
description of what SDS does in denatured electrophoresis. - correct answer ✔SDS is an amphipathic
compound that binds to the hydrophobic portion of proteins and give a negative
charge derived from the polar head group such that proteins have a proportional charge to mass ratio.
Which of the experimental steps
listed at the right is considered the most challenging in X-ray crystallography? - correct answer
✔Determining the phases of the diffracted X-rays.
Determine which major class of proteins best describes the specific representative proteins listed.
a. Telomerase
b. Protein Kinase A
c. Actin polymer
d. Lactose permease
e. Hexokinase - correct answer ✔a. Genomic caretaker
b. Cell signaling
c. Structural protein
, d. Transport protein
e. Metabolic enzyme
Which statement most accurately describes the structure and function of O2 transport proteins. -
correct answer ✔Hemoglobin is a tetramer that can bind BPG and O2 whereas myoglobin binds O2 but
cannot bind BPG.
Assume that in the graph at the right, the curve represented by Y is
normal adult hemoglobin at pH 7.4 with normal levels of 2,3-BPG. Which of the
statements below is the most correct regarding curves X and Z? - correct answer ✔Z represents O2
binding in cells with elevated 2,3-BPG, whereas X represents O2 binding in cells with
decreased 2,3-BPG.
In one type of hemoglobin mutant the amino acid change generates a strong ionic interaction
stabilizing the T state conformation but only under conditions of lower pH, e.g., at pH 7.2 compared to
pH
7.6. What effect would this mutation have on the amount of O2 delivered to the tissue and why? -
correct answer ✔More O2 delivered to the tissue because the R-T equilibrium would be shifted to the T
state in tissues.
What is the energy requirement to
transport 3 moles of Na+ from the inside to outside? - correct answer ✔+41.2 kJ
What is the energy requirement to
transport 2 moles of K+ from the outside to inside? - correct answer ✔+3.7 kJ
The cross-linked nature of the acrylamide media in SDS-PAGE can limit
migration through the polymer matrix. Based on the figure to the right put the SDS-PAGE
answers correctly solved 2025/2026
Which separation technique exploits the density differences of biomolecules and organelles? - correct
answer ✔Centrifugation using centrifuge tubes in a rotor placed in a centrifuge.
What protein feature will cause the protein to bind to a metal in chelation affinity
chromatography—specifically, a resin with immobilized Ni2+? - correct answer ✔Recombinant proteins
engineered to have six histidines at the N or C terminus of the protein.
Sodium dodecylsulfate (SDS) plays an important role in SDS PAGE. Select the correct
description of what SDS does in denatured electrophoresis. - correct answer ✔SDS is an amphipathic
compound that binds to the hydrophobic portion of proteins and give a negative
charge derived from the polar head group such that proteins have a proportional charge to mass ratio.
Which of the experimental steps
listed at the right is considered the most challenging in X-ray crystallography? - correct answer
✔Determining the phases of the diffracted X-rays.
Determine which major class of proteins best describes the specific representative proteins listed.
a. Telomerase
b. Protein Kinase A
c. Actin polymer
d. Lactose permease
e. Hexokinase - correct answer ✔a. Genomic caretaker
b. Cell signaling
c. Structural protein
, d. Transport protein
e. Metabolic enzyme
Which statement most accurately describes the structure and function of O2 transport proteins. -
correct answer ✔Hemoglobin is a tetramer that can bind BPG and O2 whereas myoglobin binds O2 but
cannot bind BPG.
Assume that in the graph at the right, the curve represented by Y is
normal adult hemoglobin at pH 7.4 with normal levels of 2,3-BPG. Which of the
statements below is the most correct regarding curves X and Z? - correct answer ✔Z represents O2
binding in cells with elevated 2,3-BPG, whereas X represents O2 binding in cells with
decreased 2,3-BPG.
In one type of hemoglobin mutant the amino acid change generates a strong ionic interaction
stabilizing the T state conformation but only under conditions of lower pH, e.g., at pH 7.2 compared to
pH
7.6. What effect would this mutation have on the amount of O2 delivered to the tissue and why? -
correct answer ✔More O2 delivered to the tissue because the R-T equilibrium would be shifted to the T
state in tissues.
What is the energy requirement to
transport 3 moles of Na+ from the inside to outside? - correct answer ✔+41.2 kJ
What is the energy requirement to
transport 2 moles of K+ from the outside to inside? - correct answer ✔+3.7 kJ
The cross-linked nature of the acrylamide media in SDS-PAGE can limit
migration through the polymer matrix. Based on the figure to the right put the SDS-PAGE
