# A conservation charity wants to preserve an endangered orchid species. Scientists have taken small pieces of tissue from the leaves of a healthy orchid and used them to grow thousands of new orchid plants. Explain how this tissue culture process produces genetically identical plants, and explain why maintaining genetic variation in the wild population is still important for the survival of the species.

> OCR A-Level Biology B — Advancing Biology (H422) — 5.4 Cloning and biotechnology · Explain · 5 marks

> An endangered orchid species has fewer than 200 plants remaining in the wild. The charity hopes to reintroduce laboratory-grown plants into the orchid's natural habitat.

## Mark scheme (5 marks)

1. The tissue cells are taken from a single parent plant / only one parent is involved (asexual reproduction)
2. No fertilisation / fusion of gametes occurs, so no new combination of alleles is introduced
3. The new cells are produced by mitosis / cell division that copies the DNA exactly, so all offspring have the same genotype as the parent
4. Low genetic variation means the wild population may not be able to adapt to changes in the environment / new diseases / pests through natural selection
5. If all reintroduced plants are genetically identical, a single disease or environmental change could cause extinction of the whole population

## Key terms

- [genetic variation](https://www.gradenine.co.uk/glossary/genetic-variation)

## Related

- [Revision notes for OCR A-Level Biology B — Advancing Biology (H422)](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-conservation-charity-wants-to-preserve-46c2c7d6) · Published by Druglandscape Ltd.