Using Command Words to Help You Score Well on IGCSE Biology

IGCSE Biology requires you to master a variety of different question styles, including multiple choice, short answer, and more extensive open-ended responses. You will need to perform calculations, show diagrams such as Punnett squares, and interpret graphs. This can all seem extremely daunting, but with a careful, organised and targeted revision strategy (and the help of a top IGCSE biology tutor) you can be sure to do well.

One of the most important techniques you can master to help you do well on your biology exams for IGSCE is to learn how to respond to command words. If you learn to recognise command words and properly construct your answers to be responsive, it will help you score well on your exam. These are the essential command words to pay attention to for the IGCSE biology exam:


This is the most basic type of question which simply asks you to identify something, for example the pancreas is the organ that produces insulin.


These questions may ask you to go through the steps of a process or pathway, such as the nitrogen cycle or cellular division. Or they may ask you to describe a biological structure such as the cellular membrane. When answering these questions for graphs, you will need to describe what you see, for example how the rate of a reaction increases or decreases in response to changes in temperature, including mentioning values.


The point of ‘explain’ questions is to answer why or how something occurs. For example, giraffes have long necks because of selective pressure resulting in an advantage for the long-necked phenotype. For these types of questions, you will need to explain the scientific reason why or how, possibly including a diagram. You may need to apply your knowledge of a familiar process to an unfamiliar context. If asked to explain a graph, you will need to explain why a graph shows the values it does, for example a graph may show an enzymatic reaction slowing at higher temperatures because the enzyme begins to denature at a certain temperature. For ‘explain’ questions, the key word to use in your response is ‘because.’


These questions ask you to compare differences AND similarities. If you are asked to compare eukaryotic and prokaryotic cells for example, you need to mention they both have ribosomes and a cell membranes, but that eukaryotic cells have a nucleus, organelles and linear DNA, while prokaryotes have a nucleoid and circular DNA. You should prepare for typical comparisons.

Evaluate Questions

‘Evaluate’ questions ask you to take your critical thinking a step further and assess the pros and cons of a current topic such as gene therapy. To prepare for these questions, keep up to date on current topics through the news and hone your writing skills.


These questions also test your critical thinking and application skills by targeting unfamiliar topics. They aim to prompt you to apply your existing knowledge to unfamiliar contexts and find solutions. Make sure you feel comfortable and confident answering each question and that you have practiced sufficiently to recognize each question type quickly. This will save you time on test day! Connect with us to see how our IGCSE biology tutors can help you prepare in an efficient and stress-free way.