(SBI4U1) Regulation of Gene Expression Flashcards
What is a gene?
Act as instructions to make proteins
What are genes made of?
DNA
Human genome contains how many genes that code for proteins?
~35000
For a cell to function properly, what must be made at the proper time and place?
Proteins
What is the process of turning on a gene to produce RNA and protein called?
Gene expression
All _____ control the _________ of proteins using the ___ code
Cells
Synthesis
DNA
For gene expression to occur, there must be a mechanism that controls what? (3)
When to make RNA and protein
How much to make
When to stop making it
In __________, gene expression can be _________ or ___________ at different points along the ________ _________ _______
Eukaryotes
Inhibited
Accelerated
Protein synthesis pathway
Methods of Regulating Gene Expression (Eukaryotes):
What is transcriptional control?
Speed up/slow down rate of transcription (less mRNA = less protein)
Methods of Regulating Gene Expression (Eukaryotes):
What is post-transcriptional control? (2)
mRNA may be broken down if protein is not needed
Length of poly-A tail/5’ cap can change (shorter protective caps means mRNA is destroyed faster in cytoplasm)
Methods of Regulating Gene Expression (Eukaryotes):
What is post translational control? (2)
Polypeptide may be degraded
Cell may slow down the folding of the polypeptide into a functional protein (if it is not needed right away)
Prokaryotes are _____ and lack a true _______; _____________ and ___________ happen nearly ______________
Simple Nucleus Transcription Translation Simultaneously
Therefore, in prokaryotes protein production is controlled solely by what?
Transcriptional regulation
In prokaryotes:
If more protein is needed, what happens?
Transcription occurs
In prokaryotes:
If no protein is needed, what happens”
Transcription stops
