New
New
Effects of substrate concentration and temperature on rate of enzyme activity
I can explain how the rate of an enzyme reaction is affected by substrate concentration and temperature.
Lesson 5 of 8
New
New
- Year 10
- AQA
Effects of substrate concentration and temperature on rate of enzyme activity
I can explain how the rate of an enzyme reaction is affected by substrate concentration and temperature.
Lesson details
Key learning points
- The rate of a reaction is the amount of change (e.g. substrate broken down or product made) per unit of time.
- Enzyme reaction rate increases as substrate concentration increases, until an optimum when all active sites are full.
- Enzyme reaction rate increases with temperature due to more collisions, until an optimum when all active sites are full.
- Enzyme reaction rate decreases as temperature increases above the optimum, as the active site becomes denatured.
- Interpretation of graphs showing effects of substrate concentration and temperature on enzyme reaction rate.
Keywords
Rate of reaction - A measure of the amount of change that occurs per unit of time.
Concentration - A measure of the quantity of a dissolved substance in a given volume of solution.
Optimum - The conditions under which the maximum rate of reaction occurs.
Denatured - A permanent change in the shape of an enzyme that stops it from working properly.
Common misconception
Enzymes die rather than denature.
The word denature is clearly introduced and a CfU explores the word die vs denature.
Use analogies to explain effects, like a supermarket checkout for substrate concentration, or a loosely folded strip of paper that can be shaken on increased temperature. The practical is really quick to do by pupils themselves, but can also be demonstrated with really cold and really hot potato.
Teacher tip
Equipment
Content guidance
- Risk assessment required - equipment
Supervision
Adult supervision required
Licence
This content is © Oak National Academy Limited (2026), licensed on Open Government Licence version 3.0 except where otherwise stated. See Oak's terms & conditions (Collection 2).
Lesson video
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Prior knowledge starter quiz
6 Questions
Q1.What type of molecule are enzymes?
What type of molecule are enzymes?
lipids
carbohydrates
amino acids
Q2.True or false? Enzymes can affect the rate of a reaction.
True or false? Enzymes can affect the rate of a reaction.
False
Q3.Enzymes the amount of activation energy needed for a reaction to take place.
Enzymes the amount of activation energy needed for a reaction to take place.
Q4.What region on an enzyme does the substrate bind to?
What region on an enzyme does the substrate bind to?
substrate site
complex site
enzyme substrate complex site
Q5.What can be said about the shape of the active site and the substrate shape?
What can be said about the shape of the active site and the substrate shape?
they are the same
the substrate is like a lock and the enzyme is like a key
Q6.Put the steps in order to show how an enzyme works.
Put the steps in order to show how an enzyme works.
Assessment exit quiz
6 Questions
Q1.True or false? The concentration of substrate will affect the rate of reaction.
True or false? The concentration of substrate will affect the rate of reaction.
False
Q2.At high temperatures the shape of the enzyme's active site can change, and it no longer fits the substrate. We say the enzyme has become ...
At high temperatures the shape of the enzyme's active site can change, and it no longer fits the substrate. We say the enzyme has become ...
energised
unbonded
denaturalised
Q3.Match the labels to what is happening.
Match the labels to what is happening.
Q4.Which part of an enzyme does the substrate need to collide with for a reaction to take place?
Which part of an enzyme does the substrate need to collide with for a reaction to take place?
Q5.What is the rate of reaction?
What is the rate of reaction?
how much substrate has been used up
how much substrate has not been used up
how long it took for the reaction to finish
Q6.Below are two graphs showing the rates of enzyme facilitated reactions. Match the graph to the factor affecting the rate of reaction.
Below are two graphs showing the rates of enzyme facilitated reactions. Match the graph to the factor affecting the rate of reaction.
