Catalysts • Catalysts are proteins • Speed up chemical reactions • Necessary for synthesis & digestion reactions Enzymes are biological catalysts.
3
Enzymes • Specificity – Enzyme shape matches substrate shape – Enzymes can be reused • Enzymes and substrates bind at the active site Enzyme
Enzymes are like…
Enzymes & Chemical Reactions • Enzyme names end in -ase. – sucrase (enzyme) – sucrose (substrate) • Enzymes are not changed by the reaction. • Substrates are changed – digested – synthesized
Examples of Enzymes Active site substrate
Examples of enzymes substrate digestion reaction active site enzyme unchanged
Enzymes in action • Catalyze synthesis and digestion reactions • Lewport Biology Place animation
Environmental Effects on Enzymes • Temperature • p. H – p. H of 1 -6 is an acid – p. H of 7 is neutral – p. H of 8 -14 is a base – Enzymes work best at an optimum temp & p. H
Temperature Above the optimum temperature the enzyme denatures (changes shape). Activity 5. 5 on Pearson. Successnet