BIOL 240 Study Guide - Midterm Guide: Lac Operon, Dna-Binding Domain, Operon
Document Summary
If you have a cell and it has dna, not all are made at once. Cell want to have conservation of energy-meaning it won"t make every single protein. Visual: feedback inhibition at regulation of enzyme activity (protein: regulation of gene expression regulation of enzyme production (gene) Expressing gene whatever is out there (conservation of energy) Natural selection favors bacteria producing only what"s needed by the cell: because spend less energy. Operons cluster of gene regulated by promoters: dna with operator, promoter, and functioned gene. Operator: the regulatory switch on, off switch. Repressible operons tryptophan: normally on made the gene, can be turned off when it doesn"t need to make anymore. Inducible operons lactose: normally off, can be turn on. Tryptophan operon on: low level tryptophan, repressor inactive-->operon on. If there are left over tryptophan it will help the allosteric site as a corepressor to help store energy as active repressor no rna made.
