Questions with Guaranteed Pass
Solutions 2025-2026 Updated.
Enzyme - Answer a biological macromolecule that acts as a catalyst for a biochemical
reaction; although almost all enzymes are composed of protein some RNA molecules are
catalytically active.
Substrate - Answer reactant in a chemical reaction upon which an enzyme acts
cofactor - Answer Non-protein helpers that may be bound tightly to the enzyme as a
permanent resident, or may bind loosely and reversibly along with the substrate.
Apoenzyme - Answer protein portion of an enzyme
Holoenzyme - Answer enzyme with its cofactor
free energy - Answer energy that is available to do work
transition state - Answer high-energy, unstable state (an intermediate form between the
substrate and the product) occurring during a chemical reaction
free energy of activation (activation energy) - Answer The amount of energy that reactants
must absorb before a chemical reaction will start
enzyme-substrate complex - Answer A temporary complex formed when an enzyme binds to
its substrate molecule(s).
Active site of an enzyme - Answer the region of an enzyme that attaches to a substrate
induced fit - Answer Caused by entry of the substrate, the change in shape of the active site
of an enzyme so that it binds more snugly to the substrate.
, Michaelis constant (Km) - Answer the substrate concentration [X] at which the velocity (V) is
50% of the maximum reaction velocity (Vmax)
Lineweaver-Burk equation - Answer 1/v = (Km/Vmax)(1/[S]) + 1/Vmax
turnover number - Answer the number of substrate molecules an enzyme can convert into
product per second
Kcat/Km - Answer A measure of enzyme efficiency
sequential reactions - Answer all substrates must bind to the enzyme before any product is
released
double-displacement reaction - Answer the ions of two compounds exchange places in an
aqueous solution to form two new compounds
allosteric enzymes - Answer have both an active site for substrate binding and an allosteric
site for binding of an allosteric effector (activator, inhibitor)
covalent catalysis - Answer the active site contains a nucleophile that is briefly covalently
modified
general acid-base catalysis - Answer a molecule other than water plays the role of a proton
donor or acceptor
metal ion catalysis - Answer metal ions function in a number of ways including serving as an
electrophilic catalyst
Catalysis by approximation and orientation - Answer enzyme brings 2 substrates together in
an orientation that facilitates catalysis
binding energy - Answer the energy that holds a nucleus together, equal to the mass defect
of the nucleus.