One of the reasons why IGCSE Biology exams can be difficult to revise for, is that there seems to be a lot of vocabulary and concepts to memorise. However, in addition to retaining all the necessary information related to the IGCSE Biology course, being able to apply the knowledge gained from Biology classes appropriately is also crucial to gaining top marks.

Firstly, students should make sure to pay attention to the command words used – if a IGCSE Biology student describes a process or pathway when asked to explain how or why something occurs, then their answers will not score highly. Further, make sure all answers are relevant and that attention is paid to the number of marks allocated for each question on the Biology paper.

Let’s take a look at a past IGCSE Biology exam question:

Plants can be genetically modified (GM) to make them resistant to pests. 

Describe an investigation that could be carried out to find out if GM plants produce better yield than normal plants.

Your answer should include experimental details and be written in full sentences. (6)

This is what the student answered in response:

It is also called genetic engineering. It is an agricultural process used to improve crop yield by making crops insect- or disease-resistant. It involves cutting useful genes from one organism’s chromosome and combining them with cells of another.  Genetically modified plants are better because they are resistant to diseases, grow more quickly, and can grow in harsher environments.

Although the statements above are relevant to the topic, the response primarily discusses how genetic modification works and the benefits from GM. It does not actually answer the question, as it does not  describe any way in which one could investigate potential differences in production between GM and normal crops.

Now, let’s consider the following response:

One way to investigate whether GM really improves food production is to compare crops that are genetically modified to ones that are not. To do this, you’ll need separate fields for GM crops and normal crops. The plants will need to be equal in number, species and growth conditions (e.g. same temperature and amount of light). If they can be controlled (e.g. grown in a greenhouse away from pests and potential diseases), that would be best. Measure and record the amount and sizes of fruits after a week, two weeks, and a month, and see if there are significant differences between the two types of crops or not. If GM can improve production, then there should be more crops, bigger crops and/or better crops in the GM fields than the normal fields.

Although the question does concern the genetic modification of crops, it’s actually assessing an IGCSE Biology student’s skills in applying experimental methods in order to investigate the potential benefits of GM. This means candidates need to design a simple experiment which will allow farmers or researchers to scientifically measure crop production and compare the results. The response above is much more appropriate than the first, and outlines the variables and the methodology clearly.

IGCSE Biology students often find application questions to be a particular challenge. While most IGCSE Biology exam questions draw upon direct recall and knowledge of the syllabus, application questions require that students prove that they can both pay close attention to command words, as well as make solid and reasoned inferences. Consequently, those studying IGCSE Biology regularly turn to outside tuition for help with this exact question type. 

At BartyED, we have a wealth of experience in supporting students to achieve their potential across their IGCSEs, including in Biology. Our approach centres on mastering topics, rather than simple memorisation. This makes our tutors highly adept at guiding students to maximise their marks on application questions on Biology IGCSE. 

If you or your child would like to learn more about our Biology programmes, or our IGCSE offerings more generally, do not hesitate to get in touch via email (enquiries@bartyed.com), or phone (+852 2882 1017). Our tutors are available to offer unparalleled support through IGCSE and beyond.

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