WGU C785 Biochemistry OA
1. Which level of protein structure is dis- Primary
rupted through the hydrolysis of pep-
tide bonds? The primary structure of a protein
is the sequence of amino acids
Quaternary held together by peptide bonds.
Peptide bonds are formed by de-
Tertiary hydration reactions and disrupted
by hydrolysis.
Primary
Secondary
2. A mutation in the beta-hemoglobin The original amino acid in a
gene, which results in the replacement healthy patient is glutamate, which
of the amino acid glutamate in position is negatively charged. The mutat-
6 with the amino acid valine, leads to ed amino acid is valine, which is
the development of sickle cell anemia. non-polar. Valine is causing sickle
The structures of glutamate and valine cell anemia. The best amino acid
are shown below. to replace valine so that the patient
is healthy again would be the one
If the beta hemoglobin gene in a patient most like glutamate, so any nega-
with sickle-cell anemia were to be edit- tively charged amino acid.
ed so that the valine in position 6 was
replaced with a different amino acid,
which replacement for valine would be
expected to have the best clinical out-
come, in theory, for the patient? (As-
sume the valine can potentially be re-
placed with any amino acid other than
glutamate.)
3. Secondary, tertiary, and quaternary lev- Placement of the protein in a solu-
els of protein structure can all be im- tion with a low pH
pacted by exposing a protein to which
treatment? Changes in pH affect hydrogen
bonds and ionic bonds. Hydrogen
Change of a hydrophobic amino acid to bonds in the backbone of amino
a different hydrophobic amino acid acids occur in secondary struc-
ture, and both hydrogen bonds
, WGU C785 Biochemistry OA
Addition of a reducing agent and ionic bonds occur in the side
chains of amino acids in tertiary
Placement of the protein in a solution structure.
with a low pH
Increase in the concentration of the
protein in solution
4. An increase in beta-pleated sheet Aggregation of the proteins in the
structure in some brain proteins can brain
lead to an increase in amyloid deposit
formation, characteristic of some neu- This question is describing
rodegenerative diseases. What is the changes in protein structure. Ag-
primary biochemical process that fol- gregation occurs when proteins
lows the increase in beta-pleated sheet clump together inappropriately,
structure that leads to the development causing plaques like amyloid de-
of the amyloid deposits? posits to accumulate.
An increase in glycogen formation in
the brain cells
Aggregation of the proteins in the brain
Secretion of glucagon, leading to ex-
cessive ketogenesis
An increase in anaerobic metabolism
of glucose in the brain
5. Which level of protein structure is de- Primary structure
termined by the sequence of amino
acids? The primary structure of a pro-
tein is simply the sequence of
Secondary structure amino acids held together by pep-
tide bonds.
Quaternary structure
Tertiary structure
, WGU C785 Biochemistry OA
Primary structure
6. Which force is most influential in de- Hydrogen bonding
termining the secondary structure of a
protein? The secondary structure of a pro-
tein is built by hydrogen bonds
Hydrophobic effect between the carboxyl groups and
amino groups on the backbones of
Disulfide bonding the amino acids.
Hydrogen bonding
Electrostatic interactions
7. Which amino acid would most likely Amino Acid structure 4
participate in hydrogen bonds?
This is a polar, uncharged amino
acid due to the OH group on
the side chain. Polar, uncharged
amino acids containing oxygen or
NH groups make hydrogen bonds.
8. Which portion of the amino acid is in- Side Chain
side the box?
The side chain is the variable
The box is surrounding the section be- group of the amino acid, also
low the Alpha Carbon called the R group. Every amino
acid has the same amino group,
carboxylic acid group, and an al-
pha carbon, but the side chain is
different.
9. Which pair of amino acids will most Both of these amino acids are
likely interact through hydrophobic non-polar and therefore can inter-
forces between their side chains? act together with a hydrophobic in-
teraction. Please note that the "S"
in the amino acid on the right is
non-polar, while the "SH" group in
answer choice D is polar. The S
1. Which level of protein structure is dis- Primary
rupted through the hydrolysis of pep-
tide bonds? The primary structure of a protein
is the sequence of amino acids
Quaternary held together by peptide bonds.
Peptide bonds are formed by de-
Tertiary hydration reactions and disrupted
by hydrolysis.
Primary
Secondary
2. A mutation in the beta-hemoglobin The original amino acid in a
gene, which results in the replacement healthy patient is glutamate, which
of the amino acid glutamate in position is negatively charged. The mutat-
6 with the amino acid valine, leads to ed amino acid is valine, which is
the development of sickle cell anemia. non-polar. Valine is causing sickle
The structures of glutamate and valine cell anemia. The best amino acid
are shown below. to replace valine so that the patient
is healthy again would be the one
If the beta hemoglobin gene in a patient most like glutamate, so any nega-
with sickle-cell anemia were to be edit- tively charged amino acid.
ed so that the valine in position 6 was
replaced with a different amino acid,
which replacement for valine would be
expected to have the best clinical out-
come, in theory, for the patient? (As-
sume the valine can potentially be re-
placed with any amino acid other than
glutamate.)
3. Secondary, tertiary, and quaternary lev- Placement of the protein in a solu-
els of protein structure can all be im- tion with a low pH
pacted by exposing a protein to which
treatment? Changes in pH affect hydrogen
bonds and ionic bonds. Hydrogen
Change of a hydrophobic amino acid to bonds in the backbone of amino
a different hydrophobic amino acid acids occur in secondary struc-
ture, and both hydrogen bonds
, WGU C785 Biochemistry OA
Addition of a reducing agent and ionic bonds occur in the side
chains of amino acids in tertiary
Placement of the protein in a solution structure.
with a low pH
Increase in the concentration of the
protein in solution
4. An increase in beta-pleated sheet Aggregation of the proteins in the
structure in some brain proteins can brain
lead to an increase in amyloid deposit
formation, characteristic of some neu- This question is describing
rodegenerative diseases. What is the changes in protein structure. Ag-
primary biochemical process that fol- gregation occurs when proteins
lows the increase in beta-pleated sheet clump together inappropriately,
structure that leads to the development causing plaques like amyloid de-
of the amyloid deposits? posits to accumulate.
An increase in glycogen formation in
the brain cells
Aggregation of the proteins in the brain
Secretion of glucagon, leading to ex-
cessive ketogenesis
An increase in anaerobic metabolism
of glucose in the brain
5. Which level of protein structure is de- Primary structure
termined by the sequence of amino
acids? The primary structure of a pro-
tein is simply the sequence of
Secondary structure amino acids held together by pep-
tide bonds.
Quaternary structure
Tertiary structure
, WGU C785 Biochemistry OA
Primary structure
6. Which force is most influential in de- Hydrogen bonding
termining the secondary structure of a
protein? The secondary structure of a pro-
tein is built by hydrogen bonds
Hydrophobic effect between the carboxyl groups and
amino groups on the backbones of
Disulfide bonding the amino acids.
Hydrogen bonding
Electrostatic interactions
7. Which amino acid would most likely Amino Acid structure 4
participate in hydrogen bonds?
This is a polar, uncharged amino
acid due to the OH group on
the side chain. Polar, uncharged
amino acids containing oxygen or
NH groups make hydrogen bonds.
8. Which portion of the amino acid is in- Side Chain
side the box?
The side chain is the variable
The box is surrounding the section be- group of the amino acid, also
low the Alpha Carbon called the R group. Every amino
acid has the same amino group,
carboxylic acid group, and an al-
pha carbon, but the side chain is
different.
9. Which pair of amino acids will most Both of these amino acids are
likely interact through hydrophobic non-polar and therefore can inter-
forces between their side chains? act together with a hydrophobic in-
teraction. Please note that the "S"
in the amino acid on the right is
non-polar, while the "SH" group in
answer choice D is polar. The S
