Biology 1002B Chapter Notes - Chapter 14: Regulatory Sequence, Operon, Repressor
Document Summary
Chapter 14. 1 - regulation of gene expression in prokaryotic cells. Transcription and translation in prokaryotes and regulated in a way that matches their life style. Prokaryotes - single celled, simple, fast generation time. Have a versatile and quick response control system, allows them to use a variety of nutrients as energy sources. Some genes are transcribed more actively when certain stimulus are present. We say that the on/ off control of these genes is at the level of transcription. Ex: metabolism of lactose by e. coli. In the absence of lactose, the 3 genes (1 codon, 1 aa) is transcribed very little. When lactose is present, that gene is transcribed more. Operon = cluster or prokaryotic genes & the dna sequences involved in their regulation. those regulating sequences include: Operator: dna regulatory sequence that controls transcription of an operon, binds to regulatory protein.