In this session, we begin with stating the purpose of gene regulation (to save and only “turn on” genes at certain times). We use a graphic to discuss the regulation of metabolic pathway (negative feedback: inhibits more production). We discuss Prokaryotic gene regulation, letting students know they need to know more about this than Eukaryotic gene regulation. We discuss the promoter region (key vocabulary: operon, operator, regressor, regulatory gene, core presser, promoter, repressible, and inducible). We show that the inducible operon can be turned on, and that the repressible operon can be inactivated. Eukaryotic gene regulation is much more complex (but students do not need to emphasize this as much as prokaryotic gene regulation on the exam). We show how the regulation of Chromatin structure is analogous to wrapping up a ball of yarn. We end with multiple choice practice.