CH 14 Flashcards
What four compotes make up an Operon (PROG)
Promoter
Repressor
Operator
Gene
Three types of genes in the lac operon
Lac Z, LacY & LacA which each make a protein to help break down lactose
What is a Regulatory Gene?
It is a Gene on the DNA that regulates another Gene further down, which creates a regulatory protein
What is a Regulatory Sequence?
A segment of a nucleic acid molecule which is capable of increasing or decreasing the expression of specific genes within an organism.
What is an example of a Positive control
Lac Operon, which deals with lactose
What is an example of a Negative control
trp Operon, which deals with the protein tryptophan
How do Eukaryotes control transcription
With transcription factors using activators, repressors to either express a gene or not.
What is Negative Regulation
Repression or Inhibitory
Repressor binds DNA at operator and blocks RNA polymerase from initiating
What is induction in gene expression?
Turning genes on. Inducer binds to the allosteric sites preventing it from inhibiting txm
What are activators
Regulatory protein which promotes txn. Functions to enhance RNA pol and promoter interaction
Repression of an allosteric activator
Binds activator turning it off
What is cAMP
•Cyclic AMP (cAMP)- a signal to tell the cell how much glucose is present.
How does cAMP regulate glucose
●High glucose- decreased synthesis of cAMP; [cAMP]
●Low glucose- increased synthesis of cAMP; [cAMP].
How are glucose levels checks in a cell
●Catabolite Activator Protein (CAP)- [cAMP receptor protein (CRP)]
