You will need certain skills to answer questions in your N5 Exam, these include:

• Predicting
• Concluding
• Selecting information from a source
• Describing relationships from table or graphs
• Suggesting aims
• Completing tables
• Completing graphs
• Discussing validity and reliability in experiments
• Suggesting experimental alterations such as controls or investigating a new variable.
• Scientific Literacy questions

Predicting

A prediction is your best guess based on the available date given to you. Often this is to predict the next number on a graph or table based on the previous changes.

Suggesting aims

The aim of an experiment is the effect of the thing you’re changing (independent variable: IV) on the thing you’re measuring (the dependent variable: DV). So an aim might look like this:

The Effect of IV on DV.

Or a more real example;

The Effect of Substrate Concentration (IV – changing) on Enzyme Activity (DV – measured).

Concluding

Drawing conclusions is based on the results of the experiment/investigation. You must always relate to the aim when concluding as sometimes the results are an indirect measurement of the main variable being investigated.

eg enzyme experiments are often measured by the release of a gas, which is an indirect measurement of enzyme activity – therefore you would mention enzyme activity, not gas released in your conclusion.

Selecting information from a source

This is where you are presented with either written, tabular or graphical data or information and you have to select the appropriate answer from the source material.

Describing relationships from table or graphs

Unlike conclusions, which always relate back to the aim, describing relationships is usually just a factual description of the data presented to you from a table or a graph.

Your answer will usually look something like this:

As the IV increases/decreases, the DV increases/decreases/stays the same.

A couple of more specific examples:

As the substrate concentration increases, the numbers of bubbles produced (indirect measurement of the enzyme activity) also increases. 

OR

As the temperature increases, the numbers of bubbles produced (enzyme activity) also increases, until the temperature reaches 37 degrees, after which the enzyme activity decreased.

Completing tables

Sometimes this can involve a calculation, and then completing a table, or may involve other skills such a predicting or selecting information from a source.

Completing graphs

Usually a line or bar graph, or a pie chart, this involves taking data from a table and plotting it on the graph grid that is in the question.

Be careful to read the question carefully and draw the right kind of graph – it will tell you – and to only include the data it asks for – again, it will tell you in the question.

Discussing control, validity and reliability in experiments

Control: set up to compare results of an experiment when no treatment is applied.

Validity: other variables are controlled to ensure any effect is likely to be due to the variable being changed.

Reliability: where consistent values in repeats of experiments are obtained.

Remember:

Co-Co (control – compare)

Va-Va (validity – variables)

Re-Re (reliability – repeat)

Suggesting experimental alterations such as controls or investigating a new variable

Often you can be asked to suggest a control experiment based on the experiment shown or described in a question, OR you can be asked to describe the set up for a new experiment with a different changing variable, again based on the original one they show in the question.

In both cases, it’s vital to remember that you can only change ONE variable at a time and that every other variable must remain constant.

Scientific Literacy Questions

These are whole questions, worth 5-8 marks, which can test all of the skills above, usually based on a bit of research or a study, in the form of a few short paragraphs which includes some data.