Gene induction

Question 1

what is gene induction

Answer 1

switching on a gene

Question 2

what is a lac operon

Answer 2

a segment of DNA found in prokaryotes which allows for regulation over translation and consist of a promotor region, operator gene and gene to be transcribed.

Question 3

what happens when lactose is absent

Answer 3

a repressor molecule attaches to the operator gene so the RNA polymerase cannot bind to the promotor region therefore transcription of the gene doesn’t occur and no mRNA is produced

Question 4

what happens when lactose is present

Answer 4

lactose binds to the repressor molecule preventing it from attaching to the operator gene so RNA polymerase can bind to the promotor region allowing transcription of the gene so mRNA can be produced.

Question 5

how can a gene be switched off

Answer 5

by a repressor molecule attaching to the promotor region or a transcription factor preventing them from attaching to the promotor region so transcription doesn’t occur.

Question 6

how to master genes switch on genes

Answer 6

mRNA transcribed from master genes are translated into signal proteins witch are transcription factors so switch on genes responsible for making proteins needed for specialising cells