Effect of Changes in Substrate Concentration on the Reaction Rate of an Enzyme Essay Example

Good Essays
Effect of changes in substrate concentration on the reaction rate of an enzyme

IB biology Internal Assessment
3/23/12

Research Question: Effect of changes in substrate concentration amount on the reaction rate of an enzyme
Introduction: In this experiment, the substrate is hydrogen peroxide. The purpose of this investigation is to find out the relationship between the substrate concentration and the rate of reaction. Substrates are molecules that are acted upon by enzymes. For instance, amylase, an enzyme found in saliva, helps break down complex starch molecules (substrates) into smaller sugar molecules (products). In other biochemical reactions, substrates require assistance of specific enzymes to form new products. When the amount of enzyme stays constant, the substrate concentration will determine the rate of reaction. However, when the number of substrate molecules exceeds the available number of enzyme, the rate of reaction will no longer increase, but stay constant. If there is a constant amount of enzyme, as the concentration of a substrate increased, the rate of reaction will increase as well. This is because of molecular collisions. If you have more reactant molecules, there are more to collide.
Aim: The effect of hydrogen peroxide on the enzyme activity of catalase
Hypothesis: When the amount of enzyme stays constant, the substrate concentration will determine the rate of reaction CONTROLLED VARIABLES | Units | Possible effect(s) on results | Amount of enzyme | 2.8g | an extra drop of enzyme can alter the rate of reaction | Size and type of test tubes | 30ml | The size and type of test tubes were constant, because they can alter the pressure | | Units | Range | INDEPENDENT VARIABLE | Hydrogen Peroxide (Substrate) Concentration | ml | 5,10,15,20,25,30 | DEPENDENDENT VARIABLE | Rate of Reaction | Seconds | 80 secs | VARIABLES:

METHOD FOR CONTROLLING VARIABLES: CONTROLLED VARIABLES | Method for control: | 1.

You May Also Find These Documents Helpful