# "Explain" questions — Pearson Edexcel International GCSE Biology (4BI1)

> 78 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 why oxygen moves from the air in the alveoli into the blood in the surrounding capillaries during gas exchange i…](https://www.gradenine.co.uk/q/explain-why-oxygen-moves-from-the-0700a3ac)
2. [Muscle is a tissue found in the wall of the stomach. The stomach works together with other organs such as the pancreas a…](https://www.gradenine.co.uk/q/muscle-is-a-tissue-found-in-10cd647b)
3. [Explain why carbon dioxide produced during respiration in the leaf's palisade mesophyll cells can be used directly for p…](https://www.gradenine.co.uk/q/explain-why-carbon-dioxide-produced-during-168b2490)
4. [Explain why the rate of diffusion of oxygen into a respiring cell increases when the cell uses oxygen more rapidly.](https://www.gradenine.co.uk/q/explain-why-the-rate-of-diffusion-17c459a7)
5. [Explain how carbon in carbon dioxide gas in the atmosphere becomes part of the carbon compounds in the body of an animal…](https://www.gradenine.co.uk/q/explain-how-carbon-in-carbon-dioxide-186728ec)
6. [Explain how GM crops can improve food production.](https://www.gradenine.co.uk/q/explain-how-gm-crops-can-improve-1bc321f4)
7. [Explain how carbon stored in the bodies of dead animals is returned to the atmosphere as carbon dioxide.](https://www.gradenine.co.uk/q/explain-how-carbon-stored-in-the-20fb63b7)
8. [Explain why lipids are described as being made from fatty acids and glycerol, and why proteins are described as being ma…](https://www.gradenine.co.uk/q/explain-why-lipids-are-described-as-244f314b)

## Related

- [Pearson Edexcel International GCSE Biology (4BI1) revision notes](https://www.gradenine.co.uk/learn/pearson-edexcel-international-gcse-biology-4bi1)
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