# "Explain" questions — Edexcel GCSE Biology (1BI0)

> 128 questions · biology

## How to answer

WHAT + WHY. Every point paired with a because. Structure: X happens because Y. This causes Z because … Assessment Objective: AO2. Every "explain" answer on this spec is marked against exactly this pattern.

## Sample questions

1. [Explain how selective breeding could be used to develop a new variety of wheat that produces a higher yield of grain.](https://www.gradenine.co.uk/q/explain-how-selective-breeding-could-be-00b3325d)
2. [During exercise, the breathing rate of a student increases. Explain how this helps to maintain efficient gas exchange in…](https://www.gradenine.co.uk/q/during-exercise-the-breathing-rate-of-01e97886)
3. [Explain why the daughter cells produced by mitosis must be genetically identical to the parent cell, and describe the ro…](https://www.gradenine.co.uk/q/explain-why-the-daughter-cells-produced-06bff663)
4. [Explain how the body's defence mechanisms prevent pathogens from entering the bloodstream when a person breathes in air …](https://www.gradenine.co.uk/q/explain-how-the-body-s-defence-mechanisms-091db727)
5. [Explain the role of decomposers and nitrifying bacteria in making nitrogen available for plant uptake.](https://www.gradenine.co.uk/q/explain-the-role-of-decomposers-and-09ba18ec)
6. [Explain how a nerve impulse is transmitted from a motor neurone to an effector.](https://www.gradenine.co.uk/q/explain-how-a-nerve-impulse-is-0d9c4e9b)
7. [A student uses a light microscope to view a sample of plant cells. Explain why the student needs to use a stain before v…](https://www.gradenine.co.uk/q/a-student-uses-a-light-microscope-0e5b6ab6)
8. [Explain how cells are organised into different levels of organisation in a multicellular organism, naming each level in …](https://www.gradenine.co.uk/q/explain-how-cells-are-organised-into-10146dfd)

## Related

- [Edexcel GCSE Biology (1BI0) revision notes](https://www.gradenine.co.uk/learn/edexcel-gcse-biology-1bi0)
- [Edexcel GCSE Biology (1BI0) past papers](https://www.gradenine.co.uk/past-papers/edexcel-gcse-biology-1bi0)
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