Safety, privacy and evidence boundary
Use fictional regulatory networks and de-identified expression datasets. Epigenetic examples are not permission to infer trauma, disease, behavior, or inheritance in individuals. Avoid deterministic or transgenerational claims not supported by evidence.
Explicit science instruction
A promoter helps recruit transcription machinery near a gene. Transcription factors bind specific DNA sequences or interact with other proteins to increase or decrease transcription. Enhancers and silencers can act over distance through chromosome folding.
Gene activity depends on combinations of regulators rather than a single universal on/off switch.
Vocabulary: promoter; enhancer; silencer; transcription factor; activator; repressor; regulatory network.
Worked example with reasoning
A fictional gene has promoter P and enhancer E. Cell type A expresses activator X and transcribes strongly; Cell B lacks X and remains low despite identical DNA sequence. The difference lies in regulatory context.
Guided question
How can two cells with the same genome transcribe the same gene at different rates?
Independent work
- Draw a promoter-enhancer model.
- Add two activators and one repressor.
- Predict expression in three cell contexts.
- State one simplification.
Misconception check
An enhancer is not always physically adjacent to the gene it regulates, and “on/off” often oversimplifies graded expression.
Formative understanding check
What does a transcription factor do in this model?
Worked response
It binds regulatory DNA or regulatory complexes and influences transcriptional activity.
Open-book formative practice only; not an official mastery attempt or grade.
Mentor evidence conference
Ask Archaemenes to challenge your information-flow model, sequence reasoning, data interpretation, and limitations.
Open ArchaemenesTeacher guidance
Foundation: use regulator cards. Core: predict expression from combinations. Extended: add combinatorial logic and chromosome looping conceptually.
Preserve learning evidence
Keep sequence work, models, corrections, and limitations in the matching Week 25 evidence field.