# A farmer wants to produce a large number of genetically identical prize-winning cattle quickly. Explain how embryo transplantation could be used to achieve this, and why the offspring produced would be genetically identical to each other.

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

> Prize-winning cattle have been selectively bred for decades to produce high-quality meat. A farmer discovers that one of his best cows has an exceptionally desirable genotype and wants to produce as many offspring with that genotype as possible in a short time.

## Mark scheme (5 marks)

1. The prize cow (donor) is given hormones to stimulate her to produce many eggs / superovulation
2. The eggs are fertilised by sperm from a prize bull (artificially inseminated / fertilised in the laboratory)
3. The embryos are removed / collected before they are allowed to develop significantly
4. Each embryo is transplanted into a surrogate / host cow's uterus to develop to term
5. The offspring are genetically identical to each other because they all contain the same DNA / genotype inherited from the same donor cow and bull / they all developed from embryos with the same genetic material

## 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-farmer-wants-to-produce-a-1b162ace) · Published by Druglandscape Ltd.