Molecular Genetics - Control Of Gene Expression In Prokaryotes (Ch. 16)

Front 1

Why is gene regulation important for bacterial cells?

Back 1

for the development of transformation and for the control of numerous life processes in all organisms; turns genes on and off in response to environmental changes.

Front 2

Name six different levels at which gene expression might be controlled.

Back 2

1. alteration of gene structure
2. level of transcription
3. mRNA processing
4. regulation of RNA stability
5. level of translation
6.protein modification

Front 3

Describe lac operon and how it controls metabolism of lactose.

Back 3

Lac operon consists of 3 structural genes --> lacZ (encodes enzyme B-galactosidase), Y(encodes lactose permease), and A(encodes enzyme thiogalactoside transacetylase).

Front 4

What is catabolite repression? How does it follow bacterial cell to use glucose in preference to other sugars?

Back 4

A system of gene control in some bacterial operons in which glucose is used preferentially and the metabolism of other sugars is repressed in the prescence of glucose.

Front 5

What is attenuation? What are mechanisms by which attenuator forms when tryptophan levels are high and the antiterminator forms when tryptophan levels are low?

Back 5

The termination of transcription before structural genes of an operon are transcribed.