Stem cells are found in both embryos and in adult organisms. Explain why stem cells are important in medicine.

WJEC GCSE Biology (Wales) — 2.2.2 Stem cells · Explain · 4 marks · View as Markdown

Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).

Model answer (4 marks)

Stem cells are unspecialised or undifferentiated cells.
They have the capacity to differentiate into many different cell types.
Because of this, they can be used to replace damaged or diseased cells or tissues.
For example, bone‑marrow transplants use stem cells to treat leukaemia.

Examiner tips

Use the exact terms 'unspecialised' and 'undifferentiated'.
Show the link between differentiation ability and therapeutic use.
Give a clear, named example such as bone‑marrow transplant for leukaemia.

Common mistakes

Confusing stem cells with mature cells.
Omitting the word 'undifferentiated'.
Using a vague example like 'tissue repair' instead of a specific medical application.

Mark scheme (4 marks)

Stem cells are unspecialised / undifferentiated cells
Stem cells can differentiate into many / different types of cell
Stem cells can be used to replace damaged or diseased cells / tissues
A named example of a medical use, e.g. treating leukaemia using bone marrow transplant / replacing nerve cells after spinal injury / treating burns using skin cells grown from stem cells

Key terms in this question

stem cell