IGCSE Edexcel Biology 'CORMMSS' Complete Guide | Crucial Exam Technique

Summary

This video guides students through the CORMs question type in the IGCSE Biology exam, focusing on how to design an investigation. The CORMs acronym stands for Change, Organism, Repeat, Measurement, and Same, which helps structure responses effectively. Using a plant growth example, the video explains how to identify variables, repeat experiments, measure growth, and maintain fair conditions. It emphasizes the importance of practicing past papers to master this question type, as it offers an easy six marks for well-prepared students.

Takeaways

• 😀 CORMS stands for Change, Organism, Repeat, Measurement, Same (for control variables) and Same (for control variables), and is crucial for answering IGCSE Biology design of investigation questions.
• 😀 The CORMS question typically doesn't require prior knowledge, making it unique from other types of questions in biology.
• 😀 In CORMS, 'Change' refers to the independent variable, which is what you intentionally alter in the experiment (e.g., concentration of plant growth substances).
• 😀 'Organism' refers to identifying the species of plant and stating control variables like using the same type, size, or age of the plant.
• 😀 'Repeat' ensures the reliability of results, with three repetitions generally being a good standard for IGCSE experiments.
• 😀 'Measurement' refers to the dependent variable, which is what you measure in the experiment (e.g., root growth), with quantifiable units like the number of roots or their length.
• 😀 'Measurement' also includes specifying the time duration of the experiment, where a reasonable period like one day is ideal for root growth to show results.
• 😀 The 'Same' variables are the control variables that should remain constant to ensure fairness, such as temperature and water availability for the plants.
• 😀 Properly identifying and controlling variables like temperature and water is key to making sure that only the concentration of plant growth substances affects root growth.
• 😀 Mastering CORMS is essential for securing full marks on IGCSE Biology Paper 1, and practice with past papers is highly recommended to ensure success.

Q & A

What is the CORMS question in IGCSE Biology?

The CORMS question in IGCSE Biology refers to an investigation design question, which tests students' ability to structure a scientific experiment. CORMS stands for Change, Organism, Repeat, Measurement, and Same, which are key elements to consider when designing an experiment.

Why is the CORMS question important in IGCSE Biology exams?

The CORMS question is important because it is consistently featured in Paper 1 of the IGCSE Biology exam. It requires students to apply their scientific reasoning skills and focus on how to design an experiment, rather than relying on prior knowledge of specific content.

What does 'Change' refer to in the CORMS method?

'Change' refers to the independent variable in an experiment. It is the factor that you intentionally alter or manipulate in order to observe its effect on the dependent variable. For example, in the given script, the concentration of plant growth substances is the 'change'.

How does 'Organism' apply in the CORMS method?

'Organism' refers to the organism being used in the experiment and any necessary controls to ensure that the experiment remains fair. For instance, using the same species, age, and size of plants would ensure consistency in the experiment.

What does 'Repeat' mean in CORMS?

'Repeat' emphasizes the importance of replicating the experiment multiple times to ensure the results are reliable. In the IGCSE Biology exam, repeating the experiment three times is often a safe approach.

What is the role of 'Measurement' in CORMS?

'Measurement' refers to the dependent variable, which is what you are measuring during the experiment. It should be quantifiable, like the length of roots or the number of roots, to provide clear data.

Why is the time duration ('Measurement' for time) important in the experiment design?

The time duration is crucial to allow enough time for the observed variable (e.g., root growth) to change and produce measurable data. A typical duration might be one day, depending on the experiment.

What does 'Same' refer to in the CORMS method?

'Same' refers to the control variables in an experiment. These are the factors you keep constant to ensure the fairness of the experiment, such as temperature or water availability, which could otherwise affect the results.

How does 'CORMS' help in structuring an experiment?

CORMS helps structure an experiment by breaking it down into manageable components. It ensures that all key factors—what to change, what to measure, how to repeat the experiment, and which variables to control—are addressed, making the experiment reliable and repeatable.

What is the best way to master CORMS questions in IGCSE Biology?

The best way to master CORMS questions is through practice. By doing past papers and familiarizing yourself with different types of CORMS questions, you can become more confident in structuring your answers and earning full marks.