O Level Biology Practical 2020 Answers Fix -
Note for the author: Because exam boards (Cambridge, Edexcel, OCR, etc.) do not publicly release official mark schemes for all variants of 2020 practicals (and many papers were cancelled/modified due to COVID-19), this post focuses on model answers, common core skills, and data interpretation—which is what students actually need to learn.
Answering "Explain" Questions: Always link biological observations to concepts like enzyme-substrate complexes or active site denaturation if temperature or pH is involved. o level biology practical 2020 answers
Technique: Students performed the Benedict’s test. Successful responses required a structured table with correct headings (e.g., sample name, time taken for color change, and final glucose concentration). Note for the author: Because exam boards (Cambridge,
Improving Accuracy: To count bubbles accurately at high concentrations, one could use a gas syringe to measure the exact volume of gas instead of counting by eye. Citrus Fruit Analysis Common 2020 Mistake: Adding CuSO₄
: Using Benedict's solution to identify glucose concentrations in "urine" samples. Citrus Fruit Analysis
Common 2020 Mistake: Adding CuSO₄ before NaOH. That gives a false negative because copper ions will not complex with the peptide bonds correctly.