Misconceptions
The process of splicing mRNA into multiple sections to code for different proteins is known as this.
What is alternative splicing?
The addition of methyl groups onto DNA which silences gene expression.
What is DNA methylation?
This operon is especially useful for the digestion of lactose, with it producing enzymes known as lactase.
What is the lac operon?
What is a promoter?
DNA is transcribed to RNA which is translated to proteins.
These sequences are not part of the operon and usually fall behind it, albeit close. They usually code for the repressor.
What are regulatory sequences?
The addition of acetyl groups onto DNA which increases gene expression.
What is DNA acetylation?
This type of operon is typically off and has to be activated to be turned on.
What is an inducible operon?
These types of sequences increase the transcription rate of a gene.
What are enhancer sequences?
In mRNA, three nucleotides often code for a gene. These match with complementary triplets of RNA found in tRNA.
What are codons?
These types of proteins bind to DNA which prevent certain sequences from being expressed as well as keeping it tighter packed.
What are histones?
This type of RNA can bind to mRNA, which can lead to the entire mRNA strand not being translated, effectively silencing the entire gene from being expressed.
What is microRNA (miRNA)?
This type of operon is typically on and has to be activated to be turned off.
What is a repressible operon?
These types of sequences decrease the transcription rate of a gene.
What are silencers?
The process in which ribosomes (rRNA) attach to mRNA to begin translation.
What is initiation stage of translation?
Single mRNA molecules have multiple coding regions (multiple start and stop codons). This would indicate that mRNA strands can do this.
What is one single mRNA strand coding for multiple proteins?
Pre-Translational, Post-transcriptional, 'killer' protein, methods are all used by eukaryotic cells for this purpose.
How can eukaryotic cells regulate gene expression?
The presence of this causes the lac operon to be activated which increases the production of enzymes.
What is lactose?
This physical mechanism/coiling allows for the promoter and enhancer to get closer together.
What is DNA bending?
In this stage of translation, the amino acid attached to each tRNA anti-codon form a long polypeptide chain of amino acids and end until finding a stop codon.
What is the elongation stage of translation?
Operons are found mostly in these types of cells.
What are prokaryotic cells?
A common goal of gene regulation is this.
What is homeostasis?
An operon can be constantly activated or repressed due to this.
What is a regulatory gene mutation?
These operons are active all the time for this reason.
The inclusion of a 5' cap, a polyadenylation tail, splicing through the removal of introns are ways for regulating this process.
What are post transcriptional measures found in Eukaryotes to ensure smooth translation without error?