T3 module 1

Question 1

types of prokaryote gene regulation

Answer 1

HOUSEKEEPING GENES
- required all the time for normal function
- CONSTITUTIVELY expressed
- e.g. structural pr, ribosomal pr

REGULATED GENES
- can be turned on/off
- e.g. enzymes for growth + division

Question 2

structures of glucose and lactose

Answer 2

lactose made up of 1 glucose and 1 galactose

Question 3

general metabolic pathway in E-coli

Answer 3

• glucose used as main energy source
• when glucose depleted, lactose used

*lactose metabolizing enzymes (β-galactosidase) are constitutively regulated because they are not needed at all times

Question 4

Francois and Manod experiment

Answer 4

answered how E.coli produce β-galactosidase to metabolize lactose

• grew E.coli in lactose free medium. Added, then removed lactose
• measured β-galactosidase production
• found that β-galactosidase increased with lactose presence

Question 5

define gene expression and its levels of regulation

Answer 5

how a functional gene is made, modified and activated
(transcription, translation and protein modification)
*NOT just transcription

regulation
1) transcriptional
2) translational
3) post-translational

Question 6

transcriptional controls

Answer 6

slowest + most efficient
contols mRNA produced

in eukaryotes and prokaryotes
- controls binding of proteins to the promoter

Question 7

translational controls

Answer 7

controls rate of translation and stability of mRNA

Question 8

post-translational controls

Answer 8

fastest
addition/removal or modifications