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Gene Expression in Prokaryotes

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Presentation on theme: "Gene Expression in Prokaryotes"— Presentation transcript:

1 Gene Expression in Prokaryotes

2 Prokaryotes: No nucleus No nuclear envelope
No membrane bound organelles BACTERIA

3 Operon The operon controls gene expression in prokaryotes. It has 3 parts: operator – on/off switch promoter – start genes

4 Regulator gene - codes for the repressor

5 Repressor - turns the gene off
When attached to the operator, it prevents RNA polymerase from reaching the genes Each repressor fits only one operator

6 Inducer – turns the gene on
Attaches to the repressor, removing it from the operator RNA polymerase then moves down the operator, transcribing the genes and making mRNA

7 To turn the gene off: mRNA codes for an enzyme which breaks down the inducer The repressor returns to the operator, turning the gene off

8 Regulator gene - codes for the repressor

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