What is a clone?

Learning objectives

Children should learn:

•that, in cloning, all genetic information comes from one parent •to consider some of the ethical issues relating to cloning •to ask questions to extend their thinking and refine ideas

Activities• As an extension, ask pupils what they understand by the term 'clone' and

where they have heard it, eg science fiction, Dolly the sheep. • Explain the principles of cloning, emphasising that it differs from sexual

reproduction in that all genetic information comes from one parent. Ask pupils to describe the consequences of this for variation between parents and offspring.

• Establish with pupils that methods of asexual reproduction, eg cuttings, grafting, have been used for many years with plants.

• Ask pupils to suggest five questions that they would ask a scientist about cloning, given the opportunity, and to explain why they think they are important.

• Help pupils to evaluate and refine their questions and to use some of the many internet sites providing information on the process to find the answers. Ask pupils what they have found and make a brief summary.

Outcome

Children:• explain why clones are genetically identical • describe how asexual reproduction has been

used to produce new plants • identify ethical issues relating to cloning of

animals • use the internet to answer their questions and

interpret what they have found

Points to note

• Asexual reproduction producing clones is covered in the key stage 4 programme of study. However, most pupils will have heard of cloning and teachers may wish to discuss it here.

• As an alternative, teachers could invite a scientist to talk about their work and answer pupils' questions.

• Media reports may contain excellent explanations and graphics of the process of cloning for the 'general reader'. The internet can also be a valuable resource.

• Extension: pupils could plant cuttings, eg of geranium, and show that they grow into new plants.

• Dolly the sheep, who became famous as the first mammal to be cloned from an adult cell, has died. The news was confirmed on Friday by the Roslin Institute, the Scottish research centre which created her.

• A decision was taken to "euthanase" six-year-old Dolly after a veterinary examination showed that she had a progressive lung disease, the institute said in a statement.

• She was not old - by sheep standards - to have been put down

•Dr Patrick Dixon, expert on ethics of human cloning

• Dolly became the first mammal clone when she was born on 5 July 1996. She was revealed to the public the following year.

• Post-mortem • Dr Harry Griffin, from the institute, said: "Sheep can live to 11 or 12 years of age and lung infections are

common in older sheep, particularly those housed inside. • "A full post-mortem is being conducted and we will report any significant findings" • Dolly was a sheep created totally by design - even her name was picked specifically to be appealing. • It came about during the latter stages of labour when Dolly was born. • Stockmen involved in the delivery thought of the fact that the cell used came from a mammary gland and

arrived at Dolly Parton, the country and western singer.

• Cloning row • Her birth was only announced seven months later and was heralded as

one of the most significant scientific breakthroughs of the decade. • But it also prompted a long-running argument over the ethics of

cloning, reaching further levels with the latest allegations of human cloning.

• Dolly gave birth to four lambs in her lifetime• Dolly, a Finn Dorset, bred normally on two occasions with a Welsh

mountain ram called David. • She first gave birth to Bonnie in April 1998 and then to three more

lambs in 1999. • But in January last year her condition caused concern when she was

diagnosed with a form of arthritis.