NR 503 Midterm Exam Questions and
Answers (2026) | Latest Exam Practice
Questions | Fully Verified Answers | A+
• what kinds of bonds do each of the 3 different types of side chains
make? -✓✓ionic, hydrophobic/non-polar, charged
• What are the 4 levels of protein structure? -✓✓Primary - linear
structure, Secondary - Folded into helix or pleated sheet caused by
hydrogen bonding, tertiary - 3D structure caused by side chain
interactions, quaternary - 1+ amino acid chains combine = multiple
subunits MUST have 1+ subunit
• What enviormental change breaks each type of bond? -
✓✓hydrophobic - temperature change, ionic - salt or decreased pH,
hydrogen - temperature, change in pH, disulfide - reducing agents
• what type of amino acid side chain leads to protein aggregration? -
✓✓hydrophobic bonds
• how do environmental changes affect protein folding? -✓✓Extreme
temp can cause hydrogen bonds to break apart = malformation of protein
folding
• how do mutations affect protein structure? -✓✓Can cause structure to
change. Protein loses form = loses function. May form a different
protein.
,• What is an electron? -✓✓Negatively charged atom on outer ring for
bonding
• What is energy: -✓✓Power derived fro chemical interaction
• what are covalent bonds? -✓✓chemical bond, atoms share 1+ valence
electrons
• what is an ionic bond? -✓✓bond between positive and negative
• what is a hydrogen bond? -✓✓weak bond between positive and
negative
• with an amino? -✓✓piece of amino acid, NH2 or NH3
• what is a carboyxl? -✓✓piece of amino acid, COO or COOH
• What is hydrophobic? -✓✓Doesn't like water, end with CH
• what is hydrophilic? -✓✓Water Lovering, end with OH, NH, or SH
,• what is disulfide bond? -✓✓strongest bond between reduction agents,
formed between SH's.
• what are zwitterions? -✓✓amino with positive and negative charges =
overall charge of zero
• what is a polypeptide -✓✓polymer of amino acids
• What is dehydration synthesis? -✓✓Process of forming peptide bonds
• what is hydrolysis? -✓✓adding water to destroy bonds
• what is an alpha helix? -✓✓twisted secondary structure, formed by
hydrogen bonds
• what is a beta sheet? -✓✓folded second structure shape, formed by
hydrogen bonds
• what is denaturation? -✓✓loss of shape duet o interruption of
chemical bonds; occurs via extreme salt, temp, pH
• what is aggregation? -✓✓clumping of inner or outer cellular proteins
caused by misfolded proteins leading to diseases such as Alzheimers,
ALS, Parkinson's
, • how do enzymes catalyze reactions? -✓✓bind with substrates to
decrease activation energy required and decrease reaction rate
• how do enzymes affect reaction rate and activation energy? -
✓✓decrease activation energy and decrease reaction rate
• what are the 4 steps of the enzymatic cycle? -✓✓enzyme recognizes
substrate, substrate attracts the enzyme; enzyme-substrate complex is
formed; enzyme-product complex formed; product is released, enzyme
recycled
• how do environmental changes affect enzymes? -✓✓High heat, pH
change, high salt concentration, and reducing agents can cause an
enzyme to lose its form/lose function
• what is a competitive inhibitor? -✓✓Mimics substrate and takes its
place on the active binding site
• what is a noncompetitive inhibitor? -✓✓Binds to allosteric site
causing active site to change shape = preventing substrate from binding
with enzyme
• what molecules increase/build up or decrease given a specific
inhibitor? A -> (enzyme 1) -> B -> (enzyme 2) -> C -> (enzyme 3) -> D.
Pretend Enzyme 2 is inhibited. -✓✓Inhibitor would cause a build up for
Answers (2026) | Latest Exam Practice
Questions | Fully Verified Answers | A+
• what kinds of bonds do each of the 3 different types of side chains
make? -✓✓ionic, hydrophobic/non-polar, charged
• What are the 4 levels of protein structure? -✓✓Primary - linear
structure, Secondary - Folded into helix or pleated sheet caused by
hydrogen bonding, tertiary - 3D structure caused by side chain
interactions, quaternary - 1+ amino acid chains combine = multiple
subunits MUST have 1+ subunit
• What enviormental change breaks each type of bond? -
✓✓hydrophobic - temperature change, ionic - salt or decreased pH,
hydrogen - temperature, change in pH, disulfide - reducing agents
• what type of amino acid side chain leads to protein aggregration? -
✓✓hydrophobic bonds
• how do environmental changes affect protein folding? -✓✓Extreme
temp can cause hydrogen bonds to break apart = malformation of protein
folding
• how do mutations affect protein structure? -✓✓Can cause structure to
change. Protein loses form = loses function. May form a different
protein.
,• What is an electron? -✓✓Negatively charged atom on outer ring for
bonding
• What is energy: -✓✓Power derived fro chemical interaction
• what are covalent bonds? -✓✓chemical bond, atoms share 1+ valence
electrons
• what is an ionic bond? -✓✓bond between positive and negative
• what is a hydrogen bond? -✓✓weak bond between positive and
negative
• with an amino? -✓✓piece of amino acid, NH2 or NH3
• what is a carboyxl? -✓✓piece of amino acid, COO or COOH
• What is hydrophobic? -✓✓Doesn't like water, end with CH
• what is hydrophilic? -✓✓Water Lovering, end with OH, NH, or SH
,• what is disulfide bond? -✓✓strongest bond between reduction agents,
formed between SH's.
• what are zwitterions? -✓✓amino with positive and negative charges =
overall charge of zero
• what is a polypeptide -✓✓polymer of amino acids
• What is dehydration synthesis? -✓✓Process of forming peptide bonds
• what is hydrolysis? -✓✓adding water to destroy bonds
• what is an alpha helix? -✓✓twisted secondary structure, formed by
hydrogen bonds
• what is a beta sheet? -✓✓folded second structure shape, formed by
hydrogen bonds
• what is denaturation? -✓✓loss of shape duet o interruption of
chemical bonds; occurs via extreme salt, temp, pH
• what is aggregation? -✓✓clumping of inner or outer cellular proteins
caused by misfolded proteins leading to diseases such as Alzheimers,
ALS, Parkinson's
, • how do enzymes catalyze reactions? -✓✓bind with substrates to
decrease activation energy required and decrease reaction rate
• how do enzymes affect reaction rate and activation energy? -
✓✓decrease activation energy and decrease reaction rate
• what are the 4 steps of the enzymatic cycle? -✓✓enzyme recognizes
substrate, substrate attracts the enzyme; enzyme-substrate complex is
formed; enzyme-product complex formed; product is released, enzyme
recycled
• how do environmental changes affect enzymes? -✓✓High heat, pH
change, high salt concentration, and reducing agents can cause an
enzyme to lose its form/lose function
• what is a competitive inhibitor? -✓✓Mimics substrate and takes its
place on the active binding site
• what is a noncompetitive inhibitor? -✓✓Binds to allosteric site
causing active site to change shape = preventing substrate from binding
with enzyme
• what molecules increase/build up or decrease given a specific
inhibitor? A -> (enzyme 1) -> B -> (enzyme 2) -> C -> (enzyme 3) -> D.
Pretend Enzyme 2 is inhibited. -✓✓Inhibitor would cause a build up for
