define catalysts
a substances that increases the rate of a chemical reaction and is not changed by the reaction
define enzymes
proteins that are involved in all metabolic reactions, where they function as biological catalysts
enzymes are important because
without them, the reactions of metabolism would not be fast enough to sustain life
enzyme action (how it works)
the substrate binds to the complementary active site on enzyme, forming enzyme-substrate complex
optimum temperature
the temperature at which an enzyme works best
optimum pH
is the pH at which an enzyme works best
effect of increased temperature of enzymes
increases kinetic energy of particles, active site and enzyme collide more, increasing successful collision as enzyme-substrate complex formation increases, so rate of reaction increases
excessive heat on enzymes
causes the atoms of enzymes to change position thus changing shape of the active site and substrate can no longer bind to it (denaturation)
high pH on enzymes
changes shape of the active site and substrate can’t bind to it (denaturation)
lock and key hypothesis
substrates have a complementary shape to the active site of the enzyme like a lock and key