Biochemistry 2024 Questions with 100% correct Answers final
Exam
Peptide Bonds
Formed through condensation (dehydration) reaction with a nucleophilic amino group attacking an
electrophilic carbonyl. Broken through hydrolysis.
Protein Structure
Primary, Secondary, Tertiary, and Quaternary
Primary Structure
Linear sequence of amino acids
Secondary Structure
Local structure, stabilized by hydrogen bonding:
α-helices and β-pleated sheets
Tertiary Structure
Three-dimensional structure stabilized by hydrophobic interactions, acid-base interactions (salt
bridges), hydrogen bonding, and disulfide bonds
Quaternary Structure
Interactions between subunits, heat and solutes cause denaturation
,Structural Proteins
Generally fibrous, include collagen, elastin, keratin, actin, and tubulin
Motor Proteins
Capable of force generation through a conformational change. Include myosin, kinesin, and dyenin
Binding Proteins
Bind a specific substrate, either to sequester it in the body or hold its concentration at a steady state
Cell Adhesion Molecules (CAMs)
Bind cells to other cells or surfaces. Include cadherins, integrins, and selectins
Antibodies (immunoglobulins/Ig)
Target a specific antigen, which may be a protein on a surface of a pathogen (invading organism) or a
toxin
Ion Channels
Can be used for regulating ion flow into or out of a cell. There are three main types of ion channels:
ungated, voltage-gated, and ligand-gated channels
Enzyme-linked Receptors
Participate in cell signaling through extracellular ligand binding and initiation of second messenger
cascades
, G protein-coupled Receptors
Membrane-bound protein associated with a trimeric G protein. They also initiate second messenger
systems.
Enzymes
Catalysts that lower activation energy necessary for reactions, do not alter free energy (Δ G) or
enthalpy (Δ H) change that accompanies the reaction nor the final equilibrium position; rather, they
change the rate (kinetics) at which equilibrium is reached
Enzymes Types
Ligases, isomerases, lyases, hydrolases, oxidoreductases, and transferases
Ligases
Responsible for joining two large bio-molecules, often of the same type
Isomerases
Catalyze the inter-conversion of isomers, including both constitutional and stereoisomers
Lyases
Catalyze cleavage without the addition of water and without the transfer of electrons. The reverse
reaction (synthesis) is usually more biologically important
Exam
Peptide Bonds
Formed through condensation (dehydration) reaction with a nucleophilic amino group attacking an
electrophilic carbonyl. Broken through hydrolysis.
Protein Structure
Primary, Secondary, Tertiary, and Quaternary
Primary Structure
Linear sequence of amino acids
Secondary Structure
Local structure, stabilized by hydrogen bonding:
α-helices and β-pleated sheets
Tertiary Structure
Three-dimensional structure stabilized by hydrophobic interactions, acid-base interactions (salt
bridges), hydrogen bonding, and disulfide bonds
Quaternary Structure
Interactions between subunits, heat and solutes cause denaturation
,Structural Proteins
Generally fibrous, include collagen, elastin, keratin, actin, and tubulin
Motor Proteins
Capable of force generation through a conformational change. Include myosin, kinesin, and dyenin
Binding Proteins
Bind a specific substrate, either to sequester it in the body or hold its concentration at a steady state
Cell Adhesion Molecules (CAMs)
Bind cells to other cells or surfaces. Include cadherins, integrins, and selectins
Antibodies (immunoglobulins/Ig)
Target a specific antigen, which may be a protein on a surface of a pathogen (invading organism) or a
toxin
Ion Channels
Can be used for regulating ion flow into or out of a cell. There are three main types of ion channels:
ungated, voltage-gated, and ligand-gated channels
Enzyme-linked Receptors
Participate in cell signaling through extracellular ligand binding and initiation of second messenger
cascades
, G protein-coupled Receptors
Membrane-bound protein associated with a trimeric G protein. They also initiate second messenger
systems.
Enzymes
Catalysts that lower activation energy necessary for reactions, do not alter free energy (Δ G) or
enthalpy (Δ H) change that accompanies the reaction nor the final equilibrium position; rather, they
change the rate (kinetics) at which equilibrium is reached
Enzymes Types
Ligases, isomerases, lyases, hydrolases, oxidoreductases, and transferases
Ligases
Responsible for joining two large bio-molecules, often of the same type
Isomerases
Catalyze the inter-conversion of isomers, including both constitutional and stereoisomers
Lyases
Catalyze cleavage without the addition of water and without the transfer of electrons. The reverse
reaction (synthesis) is usually more biologically important
