Stem cellsSpec 17.2.5
In short
A stem cell is an unspecialised cell that divides by mitosis to produce daughter cells that can become specialised for specific functions, such as red blood cells or nerve cells. Some daughter cells stay as stem cells, so the supply is not used up. Cells become specialised because only some of their genes are expressed.
- Stem cell
- An unspecialised cell that divides by mitosis to produce daughter cells that can become specialised for specific functions.
Stem cells are unspecialised. They divide by mitosis to make daughter cells. Some of these daughter cells stay as stem cells, so the supply is not used up. Others become specialised for specific functions, such as a red blood cell or a nerve cell.
Cells become specialised because only some of their genes are expressed. This links to gene expression: the genes that are switched on decide which proteins the cell makes, and so what the cell can do.
Common mistake:Do not say that stem cells 'turn into' any cell. Say that stem cells divide by mitosis and the daughter cells can become specialised.
Written and checked against the Cambridge IGCSE Biology (0610) specification · Updated October 2026
Frequently asked questions
What is the difference between mitosis and meiosis?
Mitosis produces two genetically identical diploid cells, while meiosis produces four genetically different haploid cells. Mitosis is used for growth, repair, cell replacement and asexual reproduction. Meiosis is a reduction division used to make gametes in the testes and ovaries, halving the chromosome number from diploid to haploid.
Why is meiosis important for sexual reproduction?
Meiosis is important because it halves the chromosome number, so gametes are haploid. When a sperm fertilises an egg, the full diploid number is restored in the zygote: 46 chromosomes in humans. If gametes were diploid, the chromosome number would double in every generation. Meiosis also makes gametes genetically different.
Why are stem cells useful?
Stem cells are useful because they are unspecialised cells that divide by mitosis to produce daughter cells that can become specialised, such as red blood cells or nerve cells. Some daughter cells stay as stem cells, so the supply is not used up. They become specialised when only some of their genes are expressed.
All 4 questions on Mitosis and meiosis
