Scientific investigation and graphs

This topic covers planning and reading a scientific investigation: the independent and dependent variables, the variables kept constant, and how to make results reliable. The one question here is worth 2 marks in the November 2024 Paper 1 set. Of the 2 marks, 2 are for recalling facts and terms. The same skills appear inside questions on other topics.

The 2024 Diagnostic Report says candidates gave the effect of the auxin, the growth of the lateral branches, as the independent variable, and described how variables were controlled instead of naming them. They counted all the plants together as the sample size, though the groups were treated differently and each was small. In a data question they compared the figures with the normal range in general terms without stating the times at which glucose was within the limits. State the exact thing changed, and quote the data.

Where marks are lost: in our words, from Department of Basic Education, NSC 2024 Diagnostic Report, Part 1 (Book 1).