WGU C785 BIOCHEMISTRY PREP |ACTUAL
QUESTIONS AND VERIFIED ANSWERS |BRAND
NEW 2026-2027 UPDATE|GRADED A+
Question 1
Amino acids with non-ionizable side chains are zwitterions when they are
a) in any solution
b)in solutions with pH>pKa value of their acidic group and pH<pKa value of their basic group
c)in solutions with pH>pKa value of their acidic group and pH>pKa value of their basic group
d) in solutions with pH<pKa value of their acidic group and pH<pKa value of their basic group
e)in solutions with pH<pKa value of their acidic group and pH>pKa value of their basic group
CORRECT ANSWER
b
Question 2
According to the Henderson-Hasselbalch equation, when the concentrations of proton
acceptor and proton donor are the same, then
a) the carboxylic acid is totally neutralized
b) only salt forms are present
c) pH = pKa
d) pKa = log [proton acceptor/proton donor]
e) the pH is neutral
CORRECT ANSWER
c
1
,Question 3
what information can be gained by comparing the sequences pf proteins that have the
same or similar function in different species?
a) to determine evolutionary relationships and relatedness of species
b) to determine sequences that are conserved among species since they are likely to be
important to the function and stability of the proteins
c) to locate highly variable residues which contribute little to the structure and function of
the protein
d) all of the above
e) none of the above
CORRECT ANSWER
d
Question 4
The R group of an amino acid determines if it is
a) hydrophilic or hydrophobic
b) polar or nonpolar
c) charged or uncharged
d) an acid or a base
e) all of the above
CORRECT ANSWER
e
Question 5
What is the major driving force for protein folding?
a) the hydrogen bonds that stabilize alpha helices and beta sheets
2
, b) van der waals forces
c) ionic forces (salt bridges)
d) covalent bonds, like disulfide bonds between cysteine residues
e) the increase in the entropy of the solvent when the protein folds
CORRECT ANSWER
e
Question 6
which statement explains the cleaning action of soap on greasy dishes?
a) the soap changes the water-solubility of the grease so that it is easily dissolved by the
water
b) the soap hydrates the grease with its polar head groups and holds it in suspension
c) the soap chemically breaks down the grease into smaller, more water-soluble molecules
d) the grease is trapped inside the hydrophobic interior of micelles made of soap molecules
e) the soap protonates the grease, increasing its pKa, and thus the forward rate constant, k1,
for dissolution
CORRECT ANSWER
d
Question 7
How many fragments will result from the treatment of trypsin on the following protein?
Gly-Lys-Ala-Thr-Trp-Arg-Val-Ser-Tyr-Gln-Lys-Ile
a) 0
b) 1
c) 2
d) 3
3
QUESTIONS AND VERIFIED ANSWERS |BRAND
NEW 2026-2027 UPDATE|GRADED A+
Question 1
Amino acids with non-ionizable side chains are zwitterions when they are
a) in any solution
b)in solutions with pH>pKa value of their acidic group and pH<pKa value of their basic group
c)in solutions with pH>pKa value of their acidic group and pH>pKa value of their basic group
d) in solutions with pH<pKa value of their acidic group and pH<pKa value of their basic group
e)in solutions with pH<pKa value of their acidic group and pH>pKa value of their basic group
CORRECT ANSWER
b
Question 2
According to the Henderson-Hasselbalch equation, when the concentrations of proton
acceptor and proton donor are the same, then
a) the carboxylic acid is totally neutralized
b) only salt forms are present
c) pH = pKa
d) pKa = log [proton acceptor/proton donor]
e) the pH is neutral
CORRECT ANSWER
c
1
,Question 3
what information can be gained by comparing the sequences pf proteins that have the
same or similar function in different species?
a) to determine evolutionary relationships and relatedness of species
b) to determine sequences that are conserved among species since they are likely to be
important to the function and stability of the proteins
c) to locate highly variable residues which contribute little to the structure and function of
the protein
d) all of the above
e) none of the above
CORRECT ANSWER
d
Question 4
The R group of an amino acid determines if it is
a) hydrophilic or hydrophobic
b) polar or nonpolar
c) charged or uncharged
d) an acid or a base
e) all of the above
CORRECT ANSWER
e
Question 5
What is the major driving force for protein folding?
a) the hydrogen bonds that stabilize alpha helices and beta sheets
2
, b) van der waals forces
c) ionic forces (salt bridges)
d) covalent bonds, like disulfide bonds between cysteine residues
e) the increase in the entropy of the solvent when the protein folds
CORRECT ANSWER
e
Question 6
which statement explains the cleaning action of soap on greasy dishes?
a) the soap changes the water-solubility of the grease so that it is easily dissolved by the
water
b) the soap hydrates the grease with its polar head groups and holds it in suspension
c) the soap chemically breaks down the grease into smaller, more water-soluble molecules
d) the grease is trapped inside the hydrophobic interior of micelles made of soap molecules
e) the soap protonates the grease, increasing its pKa, and thus the forward rate constant, k1,
for dissolution
CORRECT ANSWER
d
Question 7
How many fragments will result from the treatment of trypsin on the following protein?
Gly-Lys-Ala-Thr-Trp-Arg-Val-Ser-Tyr-Gln-Lys-Ile
a) 0
b) 1
c) 2
d) 3
3
