Exam Focus: 6-Mark "Evaluate the Use of Stem Cells in Medicine"

📝 Exam Focus: 6-Mark "Evaluate the Use of Stem Cells in Medicine"

This is one of the most frequently set 6-mark extended response questions for this topic. Examiners want a balanced evaluation — arguments for AND arguments against, with a conclusion.

Arguments FOR using stem cells in medicine:

• Can potentially cure or treat diseases that are currently incurable (e.g., Parkinson's disease, type 1 diabetes, spinal cord injuries)
• Can replace damaged or diseased tissue with healthy, functional cells
• Adult stem cells (e.g., from bone marrow) can be taken from the patient's own body, reducing the risk of immune rejection
• Existing treatments (bone marrow transplants, skin grafts) have already saved many lives
• iPSCs (induced pluripotent stem cells) can be produced from adult cells, avoiding the ethical issues associated with embryos

Arguments AGAINST using stem cells in medicine:

• Ethical concerns: Embryonic stem cells are obtained by destroying a human embryo, which many people consider to be a human life
• Immune rejection risk: If stem cells come from a donor rather than the patient, the immune system may attack them
• Tumour risk: Stem cells that divide uncontrollably could form tumours (particularly a risk with pluripotent cells)
• Technical challenges: Controlling differentiation precisely is very difficult; cells may not differentiate into the desired type
• Many potential treatments are still experimental and not yet proven safe or effective in humans

Top tip for 6 marks: Present at least two points on each side, use scientific terminology, and end with a brief conclusion that weighs up the arguments. Do not just list points — try to explain why each point matters.

Edexcel 1BI0 — Paper 1 (1BI0/1) Notes

On Edexcel Paper 1, stem cells and differentiation appear in Topic 2: Cells and Control. Edexcel-specific points to note:

• Context-based ethical evaluation: Edexcel is particularly likely to present a short news article or patient case study about stem cell treatment, then ask you to "evaluate the use of stem cells in this treatment." Use the context AND your own knowledge — reference both in your answer to maximise marks.
• Therapeutic cloning questions: Edexcel covers therapeutic cloning more prominently than AQA. Be ready to explain the process (nucleus from patient's cell → inserted into enucleated egg → embryo develops → stem cells harvested) and why genetically identical cells reduce rejection risk.
• "Suggest" for differentiation: You may be asked to "suggest why embryonic stem cells are used in research rather than adult stem cells." Your answer should distinguish pluripotency (can form any cell type) from multipotency (limited to tissue type) — this is the key mark.
• Plant stem cells (meristems): Edexcel emphasises that plant stem cells at meristems can differentiate throughout the plant's life — unlike animal stem cells which mostly lose this ability after early development. This distinction is frequently tested.