1|Page
BIOC 384 EXAM 2|| QUESTIONS AND 100%
CORRECT ANSWERS ALREADY GRADED A+||
LATEST AND COMPLETE UPDATE WITH
VERIFIED SOLUTIONS GUARANTEED PASS!!!
After centrifugation, there is a 10% decrease in activity and a 75% decrease in total
protein. What is purification of the target protein? - ANSWER: 3.6-Fold
Below is a fractional saturation curve for O2 binding to adult hemoglobin. Assume
that curve Y represents a system at pH 7.4 and with a normal physiological level of
2,3-BPG. Curve X represents a system that - ANSWER: has a higher pH with a
normal physiological level of 2,3-BPG.
Consider the following interaction between a protein and its ligand: [P] + [L]
mc021-1.jpg [PL].
If [L] = 5 mM, [P] = 3 mM, and [PL] = 2 mM, what is the dissociation constant? -
ANSWER: 7.5 mM
Which separation technique exploits the solubility differences of proteins? -
ANSWER: salting out by ammonium sulfate
Which of the following is a positive effector for oxygen binding to hemoglobin? -
ANSWER: O2
One of the most difficult steps in X-ray crystallography is - ANSWER:
determining the phases of diffracted X-rays.
,2|Page
A polypeptide was digested by trypsin and chymotrypsin. Use the following
information to determine the polypeptide sequence.
Trypsin Digest Chymotrypsin Digest
LMYK CE
MGFCE LMYKW
WDER DERMGF - ANSWER: LMYKWDERMGFCE
Biochemical assays are important in the process of isolating proteins because they
- ANSWER: uniquely identify one protein.
In isoelectric focusing, a protein that is physically located in the pH gradient that is
below the pI of the protein would - ANSWER: migrate toward the cathode.
The figure below shows three proteins that are separated using gel filtration
chromatography. Which protein is the largest? - ANSWER: squares
X-ray crystallography (XRC) and nuclear magnetic resonance (NMR)
spectroscopy provide three dimensional structural information about the position of
atoms in a purified protein. Name one advantage
(adv) and one disadvantage (dvg) of each technique with regard to high resolution
protein structures. - ANSWER: XRC/adv;; large proteins, XRC/dvg;; requires
crystals, NMR/adv;; soluble protein, NMR/dvg;; small proteins
Protein-specific antibodies are useful experimental tools in biochemistry. Choose
the one statement below that most correctly describes these biochemical reagents. -
ANSWER: Polyclonal antibodies are a heterogeneous mixture of antibodies that
recognize epitopes on an antigen.
, 3|Page
Match each representative protein with the most correct specific major protein
functional class.
Record your answer in the order of a, b, c, d, and e, by choosing the numbers 1, 2,
3, 4, and 5.
Major Protein Class Representative Protein
a. Cell signaling 1. Malate dehydrogenase
b. Metabolic enzyme 2. Na+/K+ ATPase
c. Genomic caretaker 3. Tubulin
d. Structural protein 4. G protein-coupled
receptor
Transport protein 5. RNA polymerase - ANSWER: 4, 1, 5, 3, 2
Which statement most accurately describes the structure and function of O2
transport proteins. - ANSWER: Hemoglobin is a tetramer that can bind BPG and
O2 whereas myoglobin binds O2 but cannot bind BPG.
Answer the following questions about the graph shown at the right.
1. The protein with the lowest dissociation constant (Kd) is protein (A or B)?
2. The protein with the highest affinity for oxygen is protein (A or B)?
3. The protein most likely to bind oxygen cooperatively is protein (A or B)?
4. The protein most likely to be an oxygen storage protein is protein (A or B)?
5. The protein most likely to be hemoglobin is protein (A or B)?
6. The protein most likely to be myoglobin is protein (A or B)? - ANSWER: 1. A
2. A
3. B
BIOC 384 EXAM 2|| QUESTIONS AND 100%
CORRECT ANSWERS ALREADY GRADED A+||
LATEST AND COMPLETE UPDATE WITH
VERIFIED SOLUTIONS GUARANTEED PASS!!!
After centrifugation, there is a 10% decrease in activity and a 75% decrease in total
protein. What is purification of the target protein? - ANSWER: 3.6-Fold
Below is a fractional saturation curve for O2 binding to adult hemoglobin. Assume
that curve Y represents a system at pH 7.4 and with a normal physiological level of
2,3-BPG. Curve X represents a system that - ANSWER: has a higher pH with a
normal physiological level of 2,3-BPG.
Consider the following interaction between a protein and its ligand: [P] + [L]
mc021-1.jpg [PL].
If [L] = 5 mM, [P] = 3 mM, and [PL] = 2 mM, what is the dissociation constant? -
ANSWER: 7.5 mM
Which separation technique exploits the solubility differences of proteins? -
ANSWER: salting out by ammonium sulfate
Which of the following is a positive effector for oxygen binding to hemoglobin? -
ANSWER: O2
One of the most difficult steps in X-ray crystallography is - ANSWER:
determining the phases of diffracted X-rays.
,2|Page
A polypeptide was digested by trypsin and chymotrypsin. Use the following
information to determine the polypeptide sequence.
Trypsin Digest Chymotrypsin Digest
LMYK CE
MGFCE LMYKW
WDER DERMGF - ANSWER: LMYKWDERMGFCE
Biochemical assays are important in the process of isolating proteins because they
- ANSWER: uniquely identify one protein.
In isoelectric focusing, a protein that is physically located in the pH gradient that is
below the pI of the protein would - ANSWER: migrate toward the cathode.
The figure below shows three proteins that are separated using gel filtration
chromatography. Which protein is the largest? - ANSWER: squares
X-ray crystallography (XRC) and nuclear magnetic resonance (NMR)
spectroscopy provide three dimensional structural information about the position of
atoms in a purified protein. Name one advantage
(adv) and one disadvantage (dvg) of each technique with regard to high resolution
protein structures. - ANSWER: XRC/adv;; large proteins, XRC/dvg;; requires
crystals, NMR/adv;; soluble protein, NMR/dvg;; small proteins
Protein-specific antibodies are useful experimental tools in biochemistry. Choose
the one statement below that most correctly describes these biochemical reagents. -
ANSWER: Polyclonal antibodies are a heterogeneous mixture of antibodies that
recognize epitopes on an antigen.
, 3|Page
Match each representative protein with the most correct specific major protein
functional class.
Record your answer in the order of a, b, c, d, and e, by choosing the numbers 1, 2,
3, 4, and 5.
Major Protein Class Representative Protein
a. Cell signaling 1. Malate dehydrogenase
b. Metabolic enzyme 2. Na+/K+ ATPase
c. Genomic caretaker 3. Tubulin
d. Structural protein 4. G protein-coupled
receptor
Transport protein 5. RNA polymerase - ANSWER: 4, 1, 5, 3, 2
Which statement most accurately describes the structure and function of O2
transport proteins. - ANSWER: Hemoglobin is a tetramer that can bind BPG and
O2 whereas myoglobin binds O2 but cannot bind BPG.
Answer the following questions about the graph shown at the right.
1. The protein with the lowest dissociation constant (Kd) is protein (A or B)?
2. The protein with the highest affinity for oxygen is protein (A or B)?
3. The protein most likely to bind oxygen cooperatively is protein (A or B)?
4. The protein most likely to be an oxygen storage protein is protein (A or B)?
5. The protein most likely to be hemoglobin is protein (A or B)?
6. The protein most likely to be myoglobin is protein (A or B)? - ANSWER: 1. A
2. A
3. B
