Gene Regulation

Question 1

how do cells ensure energy is only spent on necessary processes

Answer 1

feedback inhibition - used by many cells to regulate which genes are expressed at diff times

Question 2

operator

Answer 2

part of dna that turns gene “on”/”off” depending on if a repressor is binded to it

Question 3

what is included in an operon

Answer 3

promoter, operator, one or more structural genes, terminator

Question 4

repressor

Answer 4

binds to operator sequence –> blocks RNA Polymerase from binding to promoter –> stops transcription from occurring

Question 5

inducer

Answer 5

binds to repressor –> changes repressors shape, causing it to fall off of operator –> RNA poly can now attach to promoter and begin transcription

Question 6

what is lactose in the lac operon

Answer 6

inducer

Question 7

what is the role of tryptophan in the regulation of the trp operon

Answer 7

causes repressor to bind to operator and REPRESS system

Question 8

enhancers

Answer 8

speed up rate of transcription

Question 9

silencers

Answer 9

slow down rate of transcription

Question 10

what is the advantage of having a system like the operon to control gene regulation

Answer 10

• controls which genes are turned on/off which REDUCES UNNECESSARY ENERGY/RESOURCE USAGE by repressing the unneeded group of genes
• controls which genes are expressed to create whatever product protein is needed instead of certain groups of genes being turned on when they SHOULDN’T BE (mucus coming out of the skin). needed groups of genes are expressed to code for necessary proteins based on the situation.