Molecules to Cells Quiz #2 Flashcards
What does Keq describe?
How much product and substrate is present at equilibrium.
Keq = [product]/[substrate]
Catalysts lower _______ of a reaction but do not change its _______.
free energy of activation/activation energy and rate constant, equilibrium constant (Keq)
What is the equation that describes how much energy is released or absorbed in a reaction using the equilibrium constant?
deltaG = -RTlnKeq
What is the major driving force that moves a catalytic reaction forward?
The bond energy differences between substrate and product
When Keq < 1, deltaG is _______ and the reaction is _______. When Keq > 1, deltaG is _______ and the reaction is _______.
positive, not favorable, negative, favorable
Name the six classes of enzymes, 1-6.
Over The Hill Lies Indian Land
- Oxidoreductases
- Transferases
- Hydrolases
- Lyases
- Isomerases
- Ligases
What do lyases do?
They add and remove groups from double bonds
What is common to all enzymes’ function?
proximity effect, because they all increase the concentration of the reactants within the active site
What is a common characteristic of transition state molecules?
They have an extra constituent attached to the reactant
What is the logic behind transition state analogs?
Enzymes bind the transition state molecules more tightly than the reactants.
What does an electrophile do?
It loves electrons (-phile) so it takes them
What does a nucleophile do?
It gives electrons
What are the two forms of microenvironment effects?
hydrophobic and charge
Explain charge microenvironment effect.
Charged or polar amino acid side chains near a functional group can alter the pKa or reactivity of that group
When you see ____, think Schiff base
-NH2
