©Themoon EXAM SOLUTIONS
25/11/2024 13:32PM
BIOC 3021- Exam 1 Questions and Answers
what type of protein structure is formed by H bonding of amino acid residues? -
Answers✓✓secondary
what are the 2 basic types of secondary protein structure? - Answers✓✓alpha helix and beta
sheet
Describe the alpha helix - Answers✓✓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 - Answers✓✓H bonds are between strands rather than within a strand
what are the 2 types of beta sheets? Which one is more stable? - Answers✓✓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)? - Answers✓✓beta turn
what protein shape contains segments of both alpha helices and beta sheets? -
Answers✓✓globular proteins
what protein structure is linear and serves as a structural role in cells? Hint: these structures
tend to have specialized tertiary structure - Answers✓✓fibrous proteins
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25/11/2024 13:32PM
what is the tertiary structure of collagen? (main component of connective tissue) -
Answers✓✓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) - Answers✓✓coiling
of alpha helices
what is the tertiary structure of fibroin and beta keratin? - Answers✓✓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? -
Answers✓✓conjugated proteins
In what state do water molecules form a rapidly changing, random network of H bonds? -
Answers✓✓liquid state
how do water molecules interact with ions? - Answers✓✓they form hydration shells around
ions (direct ionic interaction)
how do water molecules interact with hydrophobic/nonpolar solutes? - Answers✓✓they form
clathrate (cagelike/hexagonal) structures around the hydrophobe (transient, no direct
interaction)
how do water molecules interact with polar solutes? - Answers✓✓they form H bonds with the
polar solute
, ©Themoon EXAM SOLUTIONS
25/11/2024 13:32PM
how do water molecules interact with amphiphilic molecules? - Answers✓✓they form micelles
What does pH measure? - Answers✓✓hydrogen ion concentration
what system buffers the intracellular fluid of cells? - Answers✓✓phosphate buffer system
what 2 ions are involved in the phosphate buffer system? - Answers✓✓H2PO4(-) and HPO4(2-
)
what is the important buffer system of blood plasma? - Answers✓✓carbonate buffer system
what 2 molecules make up the carbonate buffer system? - Answers✓✓HCO3(-) and H2CO3
(carbonic acid)
pyrimidine structure - Answers✓✓single ring structure
purine structure - Answers✓✓double ring structure
Which bases are pyrimidines? - Answers✓✓C, U, T
Which bases are purines? - Answers✓✓G, A
nucleoside vs nucleotide - Answers✓✓nucleoside: sugar + base
nucleotide: sugar + base + phosphate
25/11/2024 13:32PM
BIOC 3021- Exam 1 Questions and Answers
what type of protein structure is formed by H bonding of amino acid residues? -
Answers✓✓secondary
what are the 2 basic types of secondary protein structure? - Answers✓✓alpha helix and beta
sheet
Describe the alpha helix - Answers✓✓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 - Answers✓✓H bonds are between strands rather than within a strand
what are the 2 types of beta sheets? Which one is more stable? - Answers✓✓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)? - Answers✓✓beta turn
what protein shape contains segments of both alpha helices and beta sheets? -
Answers✓✓globular proteins
what protein structure is linear and serves as a structural role in cells? Hint: these structures
tend to have specialized tertiary structure - Answers✓✓fibrous proteins
, ©Themoon EXAM SOLUTIONS
25/11/2024 13:32PM
what is the tertiary structure of collagen? (main component of connective tissue) -
Answers✓✓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) - Answers✓✓coiling
of alpha helices
what is the tertiary structure of fibroin and beta keratin? - Answers✓✓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? -
Answers✓✓conjugated proteins
In what state do water molecules form a rapidly changing, random network of H bonds? -
Answers✓✓liquid state
how do water molecules interact with ions? - Answers✓✓they form hydration shells around
ions (direct ionic interaction)
how do water molecules interact with hydrophobic/nonpolar solutes? - Answers✓✓they form
clathrate (cagelike/hexagonal) structures around the hydrophobe (transient, no direct
interaction)
how do water molecules interact with polar solutes? - Answers✓✓they form H bonds with the
polar solute
, ©Themoon EXAM SOLUTIONS
25/11/2024 13:32PM
how do water molecules interact with amphiphilic molecules? - Answers✓✓they form micelles
What does pH measure? - Answers✓✓hydrogen ion concentration
what system buffers the intracellular fluid of cells? - Answers✓✓phosphate buffer system
what 2 ions are involved in the phosphate buffer system? - Answers✓✓H2PO4(-) and HPO4(2-
)
what is the important buffer system of blood plasma? - Answers✓✓carbonate buffer system
what 2 molecules make up the carbonate buffer system? - Answers✓✓HCO3(-) and H2CO3
(carbonic acid)
pyrimidine structure - Answers✓✓single ring structure
purine structure - Answers✓✓double ring structure
Which bases are pyrimidines? - Answers✓✓C, U, T
Which bases are purines? - Answers✓✓G, A
nucleoside vs nucleotide - Answers✓✓nucleoside: sugar + base
nucleotide: sugar + base + phosphate
