Clone Zone
Copy-paste for living things: growing identical plants from cuttings, and the egg-swap trick that made Dolly the sheep.
Work it through together, step by step
A free interactive activity that works the method through with a class, step by step.
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Clone Zone
A **clone** is a genetically identical copy of an organism. In 1996, Dolly the sheep proved we could even clone an adult mammal. This module covers cloning plants (the everyday kind) and cloning animals (the headline-grabbing kind), and why clones bring **no new variation**.
Cloning plants
Plants are easy to clone, in two main ways. Both give genetically identical offspring.
Which method, and why
A gardener takes _____ because the method is cheap and simple. A laboratory saving a rare orchid uses _____ instead, growing _____ into many identical plants.
All the same
A grower fills a whole field with plants cloned from one parent. Why is that a risk?
- They are genetically identical, so a disease that kills one can kill the whole field
- Cloned plants always grow more slowly than plants grown from seed
- Cloning makes plants mutate faster, so the crop becomes unpredictable
- Clones cannot photosynthesise, so the whole crop has to be fed artificially
Cloning animals
Animals are harder to clone than plants. AQA names two methods, and mixing them up is the easiest mark to lose here.
Match the method
- Taking cuttings
- Tissue culture
- Embryo transplant
- Adult cell cloning
- Growing a piece of a parent plant into an identical plant
- Growing small groups of cells into many identical plants
- Splitting an early animal embryo and implanting the parts
- Putting an adult cell's nucleus into an empty egg, as with Dolly
The right moment
In an embryo transplant, why must the cells be split apart **before** they specialise?
- While the cells are still unspecialised, each one can grow into a whole animal
- Specialised cells have lost most of their DNA, so they cannot be copied
- Unspecialised cells are smaller, so more of them fit inside a host mother
- Unspecialised cells divide too quickly to be separated any later
How Dolly was made
Put the steps of adult cell cloning into the correct order.
- Remove the nucleus from an unfertilised egg cell
- Insert the nucleus from an adult body cell of the animal to clone
- Give the egg an electric shock so it divides into an embryo
- Implant the embryo into the womb of an adult female
The prize cow
A farmer has one exceptional dairy cow and wants a whole herd just like her. Work through the decisions.
- She wants animals genetically identical to this cow, not merely similar to her. Which approach delivers that?
- She settles on cloning. She wants copies of THIS adult cow, the one standing in the field today. Which method fits?
- Her vet warns of one risk once the whole herd is cloned. What is it?
- A neighbour says the clones will "have new genes that make them even better than she is". Is that right?
True of cloning
Pick the TWO statements that are true of cloning.
- The clones are genetically identical to the organism they came from
- Cloning produces no new genetic variation in the population
- Cloning creates brand-new alleles that the original did not have
- Each clone belongs to a different species from the original
- Cloning needs genetic material from two different parents
Not to be confused
Three techniques, three different jobs. Examiners love to see them mixed up, so keep them apart.
Name the technique
A breeder crosses the two highest-yielding wheat plants each year and keeps the best offspring to breed from next season. Which technique is that, and why is it NOT cloning?
- Selective breeding: it chooses from variation that already exists rather than copying one plant
- Cloning: the offspring end up as identical copies of the two chosen parents
- Genetic engineering: a high-yield gene is being inserted into the wheat
- Tissue culture: small groups of cells are being grown on into new plants
In the exam
Copies made. Grade-9 habits for cloning: • **Plants**: **cuttings** (cheap, simple) and **tissue culture** (small groups of cells → many identical plants). • **Animals**: **embryo transplants** (split an early embryo) and **adult cell cloning** (adult nucleus → empty egg → shock → implant, like **Dolly**). • Cloning = **genetically identical, no new variation**: don't confuse it with breeding (selects variation) or engineering (inserts a gene).
Describe it in full
Describe how Dolly the sheep was produced by adult cell cloning, then explain why Dolly was genetically identical to the sheep the body cell came from.
- Give the four stages in order, starting with the egg cell.
- Name what is removed from the egg, and what is put in its place.
- Say how the egg is made to start dividing.
- Say where the embryo goes next, and what happens there.
- For the last part: the nucleus carries the genes, so the clone gets that sheep's genes and no others.