Chance events that cause allele frequencies to change result in genetic drift. Genetic drift becomes very important when the population size decreases. One type of genetic drift is the bottleneck effect. Explain how the bottleneck effect changes the population size and leads
to changes in allele frequencies and evolution.

Pls me i need this ! each cell has genes activated depending on it's job and what kind of cell it is. it is the presence of that causes the repressor protein to fall off and unblock the gene on the lac operon. if a gene is turned on then it is being an additional circular chromosome found in some bacteria that is used in genetic engineering.