One genome. Different cells.

Most cells of a multicellular organism contain the same genome, but different genes are expressed. This produces different proteins, structures and functions. Specialisation allows a coordinated organism to carry out many tasks.

Stem cells can self-renew and differentiate. Pluripotent cells can give rise to many body cell types, while multipotent adult stem cells have a narrower range. Ethical and practical limits matter when using stem cells in medicine.

INTERACTIVE MODEL

Cell specialisation

Nerve cell · Signal transmissionHuman cell gene expression programNerve cellNerveSkin cell

Explore: Switch the expressed gene program and compare cell roles.

\text{gene expression}\to\text{proteins}\to\text{cell function}

WORKED EXAMPLE

A skin cell and a nerve cell share nearly the same DNA.

They express different sets of genes.
The resulting proteins shape their different structures and jobs.

Assumed knowledge

DNA and proteins.

Learning checkpoints & source

YOUR LEARNING CHECKPOINT

Relate gene expression to cell specialisation.
Compare potency of stem cells.

QCAA Biology · Unit 1 · Cells as the basis of life ↗

READY TO TRY IT?

One genome. Different cells.

Cell specialisation

A skin cell and a nerve cell share nearly the same DNA.

Put the idea to work.