BIOL 200 UBC Midterm 2026
Exam Questions and Verified
Answers | Already Graded A+
What bonds form in a primary protein structure? - 🧠 ANSWER ✔✔covalent
bonds between the backbone, peptide bonds
What bonds form in a secondary protein structure? - 🧠 ANSWER ✔✔non
covalent bonds between backbone
,What bonds form in a tertiary protein structure? - 🧠 ANSWER ✔✔covalent
bonds between R groups (i.e. disulfide), non-covalent bonds between
backbone, R groups
What bonds form in a quaternary protein structure? - 🧠 ANSWER ✔✔-
covalent bonds between R groups (i.e. disulfide), non-covalent bonds
between backbone, R groups
-between 2+ polypeptides
How is a peptide bond formed? - 🧠 ANSWER ✔✔condensation reaction
between alpha amino group of one amino acid and carboxyl group of
another
Why are some folding patterns not obtainable by primary structures? - 🧠
ANSWER ✔✔resonance between C-O and C-N constrains flexibility, no
free rotation around C-N axis
What bonds stabilize primary structures? - 🧠 ANSWER ✔✔peptide bonds
What bonds stabilize secondary structures? - 🧠 ANSWER ✔✔H-bonds
between N-H, C=O groups
, What types of structures result from secondary protein folding? - 🧠
ANSWER ✔✔alpha helix, beta sheet
Describe the bonds of an alpha helix. - 🧠 ANSWER ✔✔carbonyl forms H-
bond with H from N-H of a residue, 4 residues further on sequence (in
same chain), side chains point outward
Describe the bonds of a beta sheet. - 🧠 ANSWER ✔✔polypeptide folds
back on itself, H-bonds form between N-H and C=O on neighbouring
polypeptide strands, side chains project upwards & downwards
What factors determine which structure forms in secondary folding? - 🧠
ANSWER ✔✔interactions between side chains of amino acid residues in
polypeptide such as: steric hinderance, charge repulsion, proline presence,
presence of other chem groups
What bonds stabilize tertiary structures? - 🧠 ANSWER ✔✔ionic bonds
between side chains, H-bonds, LDF (weaker so need more to stabilize),
covalent disulfide bond between cysteine
How does hydrophobic interactions take part in tertiary formation? - 🧠
ANSWER ✔✔most stable when hydrophobic residues face inwards,
surrounded by other parts of the protein
3
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2026. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
Exam Questions and Verified
Answers | Already Graded A+
What bonds form in a primary protein structure? - 🧠 ANSWER ✔✔covalent
bonds between the backbone, peptide bonds
What bonds form in a secondary protein structure? - 🧠 ANSWER ✔✔non
covalent bonds between backbone
,What bonds form in a tertiary protein structure? - 🧠 ANSWER ✔✔covalent
bonds between R groups (i.e. disulfide), non-covalent bonds between
backbone, R groups
What bonds form in a quaternary protein structure? - 🧠 ANSWER ✔✔-
covalent bonds between R groups (i.e. disulfide), non-covalent bonds
between backbone, R groups
-between 2+ polypeptides
How is a peptide bond formed? - 🧠 ANSWER ✔✔condensation reaction
between alpha amino group of one amino acid and carboxyl group of
another
Why are some folding patterns not obtainable by primary structures? - 🧠
ANSWER ✔✔resonance between C-O and C-N constrains flexibility, no
free rotation around C-N axis
What bonds stabilize primary structures? - 🧠 ANSWER ✔✔peptide bonds
What bonds stabilize secondary structures? - 🧠 ANSWER ✔✔H-bonds
between N-H, C=O groups
, What types of structures result from secondary protein folding? - 🧠
ANSWER ✔✔alpha helix, beta sheet
Describe the bonds of an alpha helix. - 🧠 ANSWER ✔✔carbonyl forms H-
bond with H from N-H of a residue, 4 residues further on sequence (in
same chain), side chains point outward
Describe the bonds of a beta sheet. - 🧠 ANSWER ✔✔polypeptide folds
back on itself, H-bonds form between N-H and C=O on neighbouring
polypeptide strands, side chains project upwards & downwards
What factors determine which structure forms in secondary folding? - 🧠
ANSWER ✔✔interactions between side chains of amino acid residues in
polypeptide such as: steric hinderance, charge repulsion, proline presence,
presence of other chem groups
What bonds stabilize tertiary structures? - 🧠 ANSWER ✔✔ionic bonds
between side chains, H-bonds, LDF (weaker so need more to stabilize),
covalent disulfide bond between cysteine
How does hydrophobic interactions take part in tertiary formation? - 🧠
ANSWER ✔✔most stable when hydrophobic residues face inwards,
surrounded by other parts of the protein
3
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2026. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
