# "Describe" questions — OCR A-Level Biology A (H420)

> 6 questions · biology

## How to answer

Say WHAT happens, in order. No reasoning. Structure: 1. First X. 2. Then Y. 3. Then Z. Assessment Objective: AO1. Every "describe" answer on this spec is marked against exactly this pattern.

## Sample questions

1. [Describe the function of a repressor protein in the regulation of gene expression.](https://www.gradenine.co.uk/q/describe-the-function-of-a-repressor-5e2c11d8)
2. [A student is investigating the rate of transpiration in a plant using a potometer. They measure the distance a bubble mo…](https://www.gradenine.co.uk/q/a-student-is-investigating-the-rate-9d6c13c7)
3. [A student is investigating the effect of pH on the germination of seeds. Describe the steps the student should take to e…](https://www.gradenine.co.uk/q/a-student-is-investigating-the-effect-a4a7ffef)
4. [The lac operon in E. coli is a well-studied example of gene regulation. Describe the role of the lac repressor protein i…](https://www.gradenine.co.uk/q/the-lac-operon-in-e-coli-b5ccbca5)
5. [Describe the differences in the structure and function of starch and cellulose, explaining how their chemical properties…](https://www.gradenine.co.uk/q/describe-the-differences-in-the-structure-b93c7287)
6. [A student is investigating the effect of temperature on the rate of an enzyme-controlled reaction. They plan to measure …](https://www.gradenine.co.uk/q/a-student-is-investigating-the-effect-edc8cc52)

## Related

- [OCR A-Level Biology A (H420) revision notes](https://www.gradenine.co.uk/learn/ocr-a-level-biology-a-h420)
- [OCR A-Level Biology A (H420) past papers](https://www.gradenine.co.uk/past-papers/ocr-a-level-biology-a-h420)
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