Planning Investigations

Why plan investigations 1 Proper planning ensures the information you obtain are useful 2 Planning enables you to decide what equipment and materials you need. 3 Planning considers whether the experiment can be done 4 Planning considers all factors that may affect the outcome. These are called VARIABLES Why plan investigations

1 The question: what you are going to investigate! 2 The prediction: What you expect to happen 3 Scientific explanation: Based on what you know or have learnt why you think your prediction will be correct. Steps of a plan1

4 Variables: a list of things that could affect the result and an explanation how! 5 Independent variable: the thing you are going to change. Dependent variable: the thing you are going to measure 6 Controlled variables: The things you must keep the same to make it a fair test. Steps of a plan 2

Steps of a plan 3 7 8 9 Method: What you must do Equipment: what you will use 9 Fair test: how your design ensures that the variables are controlled Steps of a plan 3

10 Range: how many times you will change your independent variable: minimum 5 times 11 Repetition: How many times you will repeat each test: minimum three times. 12 Table in which to collect results or format for recording data: This must be done before you start. Steps of a plan 4

Pilot test You may have to do a pilot test first In this case the results and evaluation of the pilot test may be used to help you improve your plan. You should describe the whole process to show the reliability of your plan. Pilot test

Enzymes Papain Urease Context We are developing investigatoin skills whilst learning about the action of enzymes Enzymes We first attempted an investigation with papain in which we analysed and evaluated data we collected Papain You are now going to do a full investigation into urease using the investigative steps you have learnt. Urease Context

1 Look at the lesson called “Investigating the action of urease” on blackboard 2 Tere will prepare the soybean extract which contains the urease. 3 I´ve given you the method to help you. Investigating urease