Understanding how living things grow helps us to understand and treat medical problems arising at birth or later in life. Cells can differentiate to specific functions. In animals this differentiation arises from stem cells, but this ability is lost at an early stage. Scientists are beginning to understand the medical potential of stem cells. There is ample opportunity to discuss ethical issues associated with growth and development and genetic modification, as well as giving consideration to the potential of gene therapy.

Guidance for students: How does scientific knowledge contribute to decisions regarding the termination of pregnancies?; How can gene therapy help treat cancer sufferers?

Learning objectives: human intervention can manipulate the outcome of reproduction.

Glossary: Embryo, foetus, genetic modification, selective breeding, stem cells.

Learning outcomes: Students will be assessed on their ability to;

• Explore the scientific evidence for the potential of stem cell research
• Understand that cells have a limit to the number of divisions they undergo; the Hayflick limit; stem cells and cancer cells have no Hayflick limit
• Understand that animal stem cells differentiate into all other types of cells, but lose this ability as the animal matures
• Explore the scientific evidence that contributes to the decision regarding the legality and age of termination of a foetus
• Discuss the potential benefits and ethical dilemmas posed by advances in genetic modification
• (Explain the potential of gene therapy for the relief of symptoms of inherited diseases such as cancer)
• Discuss whether gene therapy would prevent diseases being passed onto the next generation