Aim: What can affect the rate of enzyme reactions?

What do we mean when we say reaction rate? How can we speed up reactions? Add Enzymes Another word for reaction rate, is the speed of a reaction.

How do enzymes work? A + B AB Enzymes bind to the substrate so the chemical reaction can take place. ENZYME A + B AB

How can we speed up a chemical reaction even more? Increase enzyme concentration Increase substrate concentration

How can we speed the number of cars that can be built? Increase workers Increase car parts (Enzymes) (Substrates)

Increasing Substrate Concentration: As substrate Concentration increases, The reaction rate increases & then remains The same Enzyme A + B AB + H2O

Increasing enzyme concentration: As enzyme Concentration increases, The reaction rate increases & then remains The same Enzyme A + B AB + H2O

How can we increase the rate of a chemical reaction? How can we speed up enzyme activity?

So, how do we speed up this chemical reaction? Enzyme A + B AB + H2O

*What is the relationship between temperature & enzyme activity in the graph below? Optimum As temperature increases, enzyme activity increases up to its optimum & then decreases *Optimum means the most favorable temperature for the reaction to occur. *The optimum temperature for this enzyme = 40 0C

What is the optimal temperature for most human enzymes? 37 0C

What is the range at which this enzyme works? Between 20 - 6O 0C

Why does Enzyme activity begin to decrease after the optimum Temperature? The enzyme changes shape = DENATURATION

So, how much have you learned? What is the temperature range at which A, B, C work at? At what range are A & B active at the same time? What are their optimum temperatures? At what temperature does B begin to denature? A=2-37, B=3-98, C=37-120 A B C 3 - 37 A = 4, B = 37, C = 95 B = 38+ *(END OF PAGE 2)*

What is PH? -how acidic or basic a substance is….

What is the relationship between pH and enzyme activity? As pH increases from _______ to _________, enzyme activity increases and then decreases acidic basic

When is enzyme activity at its greatest? *At its optimum pH.

What is the optimal pH for human enzymes?

What is the range at which this enzyme works? Between 1 to 11

Why does Enzyme activity begin to decrease after the optimum pH? DENATURE: Loses shape

Pepsin & Trypsin Enzymes in our body that help hydrolyze proteins into amino acids. hydrolyze Pepsin- stomach Trypsin- small intestine

pH in stomach is about 2 Are the stomach juices acidic or basic?

So, how much have you learned? What is the pH range at which A & B work at? At what range are they both active? What are their optimum pH’s? Would enzymes A & B be found in the same location in our body? Why? A = 0 -6, B = 2-9 2 - 6 A = 3, b = 6.5 No. Enzymes are specific based on their shape & conditions.