Rates of Enzyme Reactions

4 factors affecting

Enzyme conc,

Substrate conc,

Temp,

pH

Measure ROR using hydrogen peroxide and catalase.

Measure volume of oxygen gas produced in a given time

Action of Catalase

Hydrogen Peroxide -> Oxygen + Water

Controlled Variables

- Enzyme vol and conc

- Substrate vol and conc

- pH

Hazards and Safety Precautions

- Hydrogen Peroxide is an irritant, wear eye protection and avoid contact with skin

- Careful when handling hot water baths, wash hands after handling source of catalase

Procedure to find effect of enzyme conc on ROR using amylase.

1. Drops of iodine solution into each well of a spotting tile

2. Serial dilution of amylase to produce several concentrations

3. Add same conc and volume of starch to the first boiling tube, starting the timer at the same time

4. Use a dropping pipette to put the mixture into one of the wells

5. Time how long it takes for the colour to no longer turn blue-black

6. Repeat 2 more times and calc the mean time taken

7. Repeat experiment for each conc of amylase

Controlled variables.

Temp,

pH,

Substrate vol and conc,

Vol of enzyme added