IB Biology - Data based question strategies

Data-based questions come up on Paper 2 and 3 all the time. Make sure you study the graph or information given at the start of the question.

Interpretation of graphs & Relationships

Being able to interpret graphs is a skill that you will need for the exams.

The first step is to identify the scales and axes, looking at the units.  Are the scales linear or log scales?    You must show the units in your answers.

After this, pay attention to the lines and relationship of the data:

Are the lines linear (straight?) what is the slope (gradient)?  Positive or negative?  Do the lines cross?  At what point?

Are the lines non-linear?  What is the relationship-  exponential, plateau, inverse, S cureve, hyperbolic, root function?

If you're finding difficulties in doing this, check out how to establish a relationship from a graph.

Sometimes the data does not show a simple relationship.  For example, here are a collection of past paper data base questions.

Calculations

Be sure to give the units in your answers as shown in the graphs and tables.  This may seem complicated but just copy everything after the "/" on the axes or in the heading of tables.  You will lose 1 mark for omitting the units! No reason to throw away a mark when PhewStressit is given to you!