Criterion C asks you to handle data from living systems honestly: show it clearly, describe what it says, and be careful about how much one set of results can prove.
Clear tables and graphs with units, labels and any calculations shown.
You describe the pattern with numbers and explain it using science.
You say whether the evidence supports your hypothesis and how far.
You link specific weaknesses in the method to their effect on the results.
Realistic changes that would fix the weaknesses you found, or the next question to test.
A little of the criterion is addressed. Ideas are basic, partly missing, or not linked to the task.
The main points are there but thin. Some explanations are correct; links to the task or evidence are incomplete.
Mostly accurate, well explained and consistently tied to the task, with only small gaps.
Detailed, precise and justified throughout, with ideas connected and applied to new situations or evidence.
A plain-language guide only. Your teacher marks against the official IB level descriptors.
Evaluate an enzyme investigation in which the rate of reaction was measured at five temperatures.
The results were not very good. We could do it again.
The results at 60 °C showed one anomalous reading (rate 3.2 compared with 0.4 and 0.5), which I excluded after noting it probably came from a delay in starting the timer. Only three repeats per temperature were taken, so the mean may not represent the true rate. Taking five repeats and using a water bath with a thermometer would give more reliable data about where the optimum lies.
Criterion C is Processing and evaluating. It is marked out of 8 across 5 strands (C.i, C.ii, C.iii, C.iv, C.v). Criterion C asks you to handle data from living systems honestly: show it clearly, describe what it says, and be careful about how much one set of results can prove.
Calculate a mean for repeats and show how, and consider ranges to show spread. Draw graphs with the independent variable on the x-axis, labelled with units. Describe the pattern with numbers and then explain it with biology.
Concluding a cause from only one repeat. Explaining a result by saying it was because of the experiment. Leaving anomalous results in the mean without comment.
Written by CritABCD for study and revision, in our own words. The official MYP Biology guide and assessment criteria are published by the International Baccalaureate. Official IB guide ↗