# 4-mark practice questions — Edexcel GCSE Biology (1BI0)

> 146 questions · biology

## How to answer

4-mark questions are the shortest levels-of-response band. Aim for four scientific ideas, each in its own short sentence.

## 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. [Describe how meiosis and fertilisation together ensure that offspring produced by sexual reproduction are genetically di…](https://www.gradenine.co.uk/q/describe-how-meiosis-and-fertilisation-together-08f2596c)
5. [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)
6. [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)
7. [Describe how mutations can lead to genetic variation within a population of organisms.](https://www.gradenine.co.uk/q/describe-how-mutations-can-lead-to-0ca7b327)
8. [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)

## 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)
- [Practise with AI marking (free)](https://www.gradenine.co.uk/start)