©FYNDLAY EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
BIOC 3021- Exam 1 Questions And Answers
(Guaranteed A+)
What type of protein structure is formed by H bonding of amino acid residues? -
answer✔secondary
what are the 2 basic types of secondary protein structure? - answer✔alpha helix and beta sheet
Describe the alpha helix - answer✔a spiral structure formed by a single polypeptide chain;
each C=O is H bonded to the N-H group that is 4 amino acids down the strand
Describe the beta sheet - answer✔H bonds are between strands rather than within a strand
what are the 2 types of beta sheets? Which one is more stable? - answer✔Parallel (H bonds
angled) and antiparallel n(H bonds are colinear with the covalent bonds-this one is more stable)
what do we call a sharp bend in a polypeptide chain that allows the strand to reverse its
direction (fold up on itself)? - answer✔beta turn
what protein shape contains segments of both alpha helices and beta sheets? -
answer✔globular proteins
what protein structure is linear and serves as a structural role in cells? Hint: these structures
tend to have specialized tertiary structure - answer✔fibrous proteins
what is the tertiary structure of collagen? (main component of connective tissue) -
answer✔Collagen is a fibrous protein that consists of a special helix of 3 intertwined
polypeptide chains (triple helix that is right handed and held together by H bonds)
what is the tertiary structure of alpha keratin? (found in hair, fingernails) - answer✔coiling of
alpha helices
what is the tertiary structure of fibroin and beta keratin? - answer✔primarily stacked beta
sheets
In addition to the polypeptide chain, what type of protein contains a component such as
carbohydrate, lipid, nucleic acid, phosphate groups, metal ions, heme, or flavin? -
answer✔conjugated proteins
1|Page
, ©FYNDLAY EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
In what state do water molecules form a rapidly changing, random network of H bonds? -
answer✔liquid state
how do water molecules interact with ions? - answer✔they form hydration shells around ions
(direct ionic interaction)
how do water molecules interact with hydrophobic/nonpolar solutes? - answer✔they form
clathrate (cagelike/hexagonal) structures around the hydrophobe (transient, no direct
interaction)
how do water molecules interact with polar solutes? - answer✔they form H bonds with the
polar solute
how do water molecules interact with amphiphilic molecules? - answer✔they form micelles
What does pH measure? - answer✔hydrogen ion concentration
what system buffers the intracellular fluid of cells? - answer✔phosphate buffer system
what 2 ions are involved in the phosphate buffer system? - answer✔H2PO4(-) and HPO4(2-)
what is the important buffer system of blood plasma? - answer✔carbonate buffer system
what 2 molecules make up the carbonate buffer system? - answer✔HCO3(-) and H2CO3
(carbonic acid)
pyrimidine structure - answer✔single ring structure
purine structure - answer✔double ring structure
Which bases are pyrimidines? - answer✔C, U, T
Which bases are purines? - answer✔G, A
nucleoside vs nucleotide - answer✔nucleoside: sugar + base
nucleotide: sugar + base + phosphate
what is the dominant form of DNA? - answer✔B form
distance along the helix axis for 1 complete turn of the DNA strand is called? - answer✔pitch
how long is the pitch in DNA? - answer✔10bp or 34A
what is the dehydrated form of B DNA? - answer✔A form
define palindrome - answer✔inverted repeat sequence
2|Page
ALL RIGHTS RESERVED.
BIOC 3021- Exam 1 Questions And Answers
(Guaranteed A+)
What type of protein structure is formed by H bonding of amino acid residues? -
answer✔secondary
what are the 2 basic types of secondary protein structure? - answer✔alpha helix and beta sheet
Describe the alpha helix - answer✔a spiral structure formed by a single polypeptide chain;
each C=O is H bonded to the N-H group that is 4 amino acids down the strand
Describe the beta sheet - answer✔H bonds are between strands rather than within a strand
what are the 2 types of beta sheets? Which one is more stable? - answer✔Parallel (H bonds
angled) and antiparallel n(H bonds are colinear with the covalent bonds-this one is more stable)
what do we call a sharp bend in a polypeptide chain that allows the strand to reverse its
direction (fold up on itself)? - answer✔beta turn
what protein shape contains segments of both alpha helices and beta sheets? -
answer✔globular proteins
what protein structure is linear and serves as a structural role in cells? Hint: these structures
tend to have specialized tertiary structure - answer✔fibrous proteins
what is the tertiary structure of collagen? (main component of connective tissue) -
answer✔Collagen is a fibrous protein that consists of a special helix of 3 intertwined
polypeptide chains (triple helix that is right handed and held together by H bonds)
what is the tertiary structure of alpha keratin? (found in hair, fingernails) - answer✔coiling of
alpha helices
what is the tertiary structure of fibroin and beta keratin? - answer✔primarily stacked beta
sheets
In addition to the polypeptide chain, what type of protein contains a component such as
carbohydrate, lipid, nucleic acid, phosphate groups, metal ions, heme, or flavin? -
answer✔conjugated proteins
1|Page
, ©FYNDLAY EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
In what state do water molecules form a rapidly changing, random network of H bonds? -
answer✔liquid state
how do water molecules interact with ions? - answer✔they form hydration shells around ions
(direct ionic interaction)
how do water molecules interact with hydrophobic/nonpolar solutes? - answer✔they form
clathrate (cagelike/hexagonal) structures around the hydrophobe (transient, no direct
interaction)
how do water molecules interact with polar solutes? - answer✔they form H bonds with the
polar solute
how do water molecules interact with amphiphilic molecules? - answer✔they form micelles
What does pH measure? - answer✔hydrogen ion concentration
what system buffers the intracellular fluid of cells? - answer✔phosphate buffer system
what 2 ions are involved in the phosphate buffer system? - answer✔H2PO4(-) and HPO4(2-)
what is the important buffer system of blood plasma? - answer✔carbonate buffer system
what 2 molecules make up the carbonate buffer system? - answer✔HCO3(-) and H2CO3
(carbonic acid)
pyrimidine structure - answer✔single ring structure
purine structure - answer✔double ring structure
Which bases are pyrimidines? - answer✔C, U, T
Which bases are purines? - answer✔G, A
nucleoside vs nucleotide - answer✔nucleoside: sugar + base
nucleotide: sugar + base + phosphate
what is the dominant form of DNA? - answer✔B form
distance along the helix axis for 1 complete turn of the DNA strand is called? - answer✔pitch
how long is the pitch in DNA? - answer✔10bp or 34A
what is the dehydrated form of B DNA? - answer✔A form
define palindrome - answer✔inverted repeat sequence
2|Page
