AP Biology / Unit 6: Gene Expression and Regulation
6.5 Regulation of Gene Expression
Notes
- Prokaryotes: operons. The lac operon is inducible (on when lactose is present); the trp operon is repressible.
- Eukaryotes: transcription factors, enhancers, DNA methylation and histone acetylation control access to genes.
Practice
When lactose is present, the lac repressor:
Inducible operon.
Histone acetylation usually:
More access for RNA polymerase.
DNA methylation usually:
A silencing mark.
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