Gene Expression

Question 1

Summarize Gene Expression.

Answer 1

Multistep process that ultimately results in production of functional gene product (RNA/protein)

Question 2

Genes can be generally classified into what two groups?

Answer 2

1) Housekeeping genes

2) Regulated genes

Question 3

Describe Housekeeping genes

Answer 3

1) involved in basic cellular functions that are required regardless of cell type/environmental cues
2) constitutively expressed and not regulated

Question 4

Describe Regulated genes

Answer 4

1) Required only in certain cell types and/or only under certain conditions
2) subject to various control mechanisms that determine if/when these genes are expressed

Question 5

Name the 5 levels of regulation in Eukaryotes

Answer 5

Epigenetics
Transcriptional
Post Transcriptional
Translation
Post-translational

Question 6

Describe the types of Operons.

Answer 6

Repressible: transcription is usually ON but can be inhibited/repressed

Inducible: transcriptional is usually OFF but can be stimulated/induced

Question 7

What is an example of an Inducible Operon?

Answer 7

Lactose Operon (Lac Operon)

Question 8

Describe the Lac Operon

Answer 8

-Glucose is preferred carbon source for E.coli
-E.coli can use other sugars such as lactose, however, this requires more enzymes (more energy)
So, E.coli only produces the enzymes to use if other sugars if:
-Glucose is absent
-another sugar is present (i.e. lactose)