Trace differential gene expression from epigenetic changes through active genes, mRNA and protein synthesis to the specialised structure or function of a cell.
Insulin is a protein produced in beta cells in the pancreas.
Ribosomes are involved in the production of insulin.
Explain why beta cells can produce insulin but other cells in the pancreas do not.
An explanation that includes the following points:
- cell specialisation (1)
- because gene (for insulin production) switched off in (other pancreas cells) due to \{epigenetic modification / DNA methylation / histone modification (1)
- because gene (for insulin production) \{active / switched on / expressed\} in these (beta) cells (1)
- therefore transcription of (active insulin) gene / (active) mRNA produced (1)
- translation of (active) mRNA leads to synthesis of insulin protein (1)
Accept differential gene expression in these cells
Accept transcription of insulin gene only occurs in beta cells Accept reverse argument for other pancreas cells
Accept reverse argument for other pancreas cells