# A student uses a light microscope to view a sample of plant cells. Explain why the student needs to use a stain before viewing the cells, and describe how increasing the magnification of the microscope would affect what the student can see.

> Edexcel GCSE Biology (1BI0) — 1.3 Microscopy · Explain · 4 marks

> A student prepares a slide of onion cells to observe under a light microscope. The cells appear almost transparent at first, so the student adds a stain before placing the coverslip.

## Mark scheme (4 marks)

1. Stains are used because cells/cell components are (almost) transparent / colourless / difficult to see without a stain
2. The stain is absorbed by (certain) cell structures / organelles, making them show up in contrasting colour / making them easier to distinguish
3. Increasing magnification makes the image of the cell appear larger / the cell looks bigger
4. Increasing magnification means fewer cells fit into the field of view / the field of view becomes smaller

## Key terms

- [stain](https://www.gradenine.co.uk/glossary/stain)
- [magnification](https://www.gradenine.co.uk/glossary/magnification)
- [light microscope](https://www.gradenine.co.uk/glossary/light-microscope)

## Related

- [Revision notes for Edexcel GCSE Biology (1BI0)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/a-student-uses-a-light-microscope-0e5b6ab6) · Published by Druglandscape Ltd.