The Chemistry of Life, Chemical reactions and Enzymes 2-4 2-4 Chemical Reactions & Enzymes The Chemistry of Life, Chemical reactions and Enzymes 2-4

Chemical reactions need help to get started. 2-4 Chemical Reactions & Enzymes Chemical reactions need help to get started. Ex: A fire needs a match to get it started.

The energy required to get a chemical reaction STARTED 2-4 Chemical Reactions & Enzymes The energy required to get a chemical reaction STARTED Is called _________________ ACTIVATION ENERGY ACTIVATION ENERGY REACTANTS PRODUCTS

___________ HELP CHEMICAL REACTIONS HAPPEN FASTER CATALYSTS 2-4 Chemical Reactions & Enzymes ___________ HELP CHEMICAL REACTIONS HAPPEN FASTER CATALYSTS Catalysts work by ___________ the ACTIVATION ENERGY required to get a chemical reaction started. DECREASING

IT’S LIKE PUSHING A SNOWBALL UP A HILL 2-4 Chemical Reactions & Enzymes IT’S LIKE PUSHING A SNOWBALL UP A HILL Once it gets to top . . . it can roll back all by itself

CATALYSTS in Living Things 2-4 Chemical Reactions & Enzymes CATALYSTS in Living Things In living systems PROTEINS that act as catalysts to control chemical reactions are called = _________ ENZYMES

PROTEINS CAN BE ENZYMES 2-4 Chemical Reactions & Enzymes PROTEINS CAN BE ENZYMES ACTIVE SITE ENZYME SUBSTRATE ENZYME-SUBSTRATE COMPLEX ENZYME Unchanged & Reusable PRODUCTS

to only _________of _________. 2-4 Chemical Reactions & Enzymes ENZYMES fit like a lock and key to only _________of _________. Enzymes are UNCHANGED by the reaction and REUSABLE. ONE KIND SUBSTRATE

FACTORS THAT AFFECT ENZYME ACTIVITY 2-4 Chemical Reactions & Enzymes FACTORS THAT AFFECT ENZYME ACTIVITY ___ & __________ Conditions that are TOO ACIDIC or TOO HOT cause proteins to UNWIND or DENATURE pH temperature See a movie

2-4 Chemical Reactions & Enzymes Denaturing changes the shape of the ______________ so enzyme can’t bind to ____________ ACTIVE SITE SUBSTRATE _______________ (keeping pH and temperature constant) is important for maintaining ENZYME FUNCTION HOMEOSTASIS

Many enzyme NAMES end in _____ 2-4 Chemical Reactions & Enzymes -ASE Many enzyme NAMES end in _____ and the beginning of the name tells what it does DNA Polymerase= “polymerizes” joins monomers to make DNA Protease= breaks down proteins ATP synthase= synthesizes ATP