ACS Biochemistry Exam Question and
Answer 2026 | Practice Questions and
Comprehensive Solutions | Grade A+
• Ramachandran plots. CORRECT ANSWER: Φ = N-R
ψ = C-R
optimal angle to prevent steric hinderance
• Protein structure of a helix, B sheet, reverse turn. CORRECT
ANSWER: a: LEMARKHQ
B: VICYFTW
RT: PSDNG
• how many amino acids in alpha turn helix. CORRECT ANSWER: 3.6
• Super secondary structure. CORRECT ANSWER: helix turn helix
• parallel vs. antiparallel. CORRECT ANSWER: parallel wedges face
same way
antiparallel face opposite
• Isoelectric point (pI). CORRECT ANSWER: pH at which a particular
molecule carries no net electrical charge.
,• Protein Separation Techniques (ALL). CORRECT ANSWER:
Homogenization
Salting Out
Affinity Chromatgraphy
Ion Exchange
Size Exclusion/Gel Filtration
H, S, A, I, SG
He said all individuals SinG
• Protein Separation Techniques (H). CORRECT ANSWER:
Homogenization
disrupt cells, sonicator, centrifuge
• Protein Separation Techniques (S). CORRECT ANSWER: Salting out
different proteins precipitate out at different salt concentrations
• Protein Separation Techniques (A). CORRECT ANSWER: Affinity
chromatography
add a tag; histidine binds; see how well there is an affinity for the group
• Protein Separation Techniques (I). CORRECT ANSWER: ion
exchange
separation based on charge; + proteins stick to - beads
, • Protein Separation Techniques (SG). CORRECT ANSWER: Size
Exclusion/Gel Filtration
separation based on size
• Cuts (protein separation techniques). CORRECT ANSWER: cut out
what dont need/isnt protein
(use 40% concen. then keep liquid; if use 60% concen. then keep pellet)
• Dialysis. CORRECT ANSWER: protein separation based on bad with
pores
1. Moles in bag + moles in buffer
2. Divide moles by total volume - new concentration
• Electrophoresis. CORRECT ANSWER: gels - move by size with
electric current
1. Isoelectric focusing - purely pH
2. SDS page
pH separation is by pI and charge in 2d
• Protein sequencing (who cuts after what). CORRECT ANSWER:
Cyanogen bromide = methionine
trypsin = K, and R
chymotrypsin = F, M, L, W, Y
• IP. CORRECT ANSWER: Immunoprecipitation with proteins
Answer 2026 | Practice Questions and
Comprehensive Solutions | Grade A+
• Ramachandran plots. CORRECT ANSWER: Φ = N-R
ψ = C-R
optimal angle to prevent steric hinderance
• Protein structure of a helix, B sheet, reverse turn. CORRECT
ANSWER: a: LEMARKHQ
B: VICYFTW
RT: PSDNG
• how many amino acids in alpha turn helix. CORRECT ANSWER: 3.6
• Super secondary structure. CORRECT ANSWER: helix turn helix
• parallel vs. antiparallel. CORRECT ANSWER: parallel wedges face
same way
antiparallel face opposite
• Isoelectric point (pI). CORRECT ANSWER: pH at which a particular
molecule carries no net electrical charge.
,• Protein Separation Techniques (ALL). CORRECT ANSWER:
Homogenization
Salting Out
Affinity Chromatgraphy
Ion Exchange
Size Exclusion/Gel Filtration
H, S, A, I, SG
He said all individuals SinG
• Protein Separation Techniques (H). CORRECT ANSWER:
Homogenization
disrupt cells, sonicator, centrifuge
• Protein Separation Techniques (S). CORRECT ANSWER: Salting out
different proteins precipitate out at different salt concentrations
• Protein Separation Techniques (A). CORRECT ANSWER: Affinity
chromatography
add a tag; histidine binds; see how well there is an affinity for the group
• Protein Separation Techniques (I). CORRECT ANSWER: ion
exchange
separation based on charge; + proteins stick to - beads
, • Protein Separation Techniques (SG). CORRECT ANSWER: Size
Exclusion/Gel Filtration
separation based on size
• Cuts (protein separation techniques). CORRECT ANSWER: cut out
what dont need/isnt protein
(use 40% concen. then keep liquid; if use 60% concen. then keep pellet)
• Dialysis. CORRECT ANSWER: protein separation based on bad with
pores
1. Moles in bag + moles in buffer
2. Divide moles by total volume - new concentration
• Electrophoresis. CORRECT ANSWER: gels - move by size with
electric current
1. Isoelectric focusing - purely pH
2. SDS page
pH separation is by pI and charge in 2d
• Protein sequencing (who cuts after what). CORRECT ANSWER:
Cyanogen bromide = methionine
trypsin = K, and R
chymotrypsin = F, M, L, W, Y
• IP. CORRECT ANSWER: Immunoprecipitation with proteins
