Fun zone :D
Gene Regulation
Fill in the Blank
Operons
Noncoding RNAs
100
How much % is gene regulation on the AP exam?
12-16%
100
Which of the following are involved in post transcriptional control?
a. control of RNA splicing
b. control of RNA shuttling
c. control of RNA stability
d. all of the above
D. all of the above
100
Most cells within an organism ___________ capable of becoming any cell type.
[NEEDS TO BE FIXED]
genetically identical and totipotent
100
What does the promoter do?
[NEEDS TO BE CHECKED]
It binds to the promoter region to initiate transcription of a certain gene.
100
What is one type of chromatin modification?
Histone acetylation loosens chromatin structure, promoting transcription.
DNA methylation reduces transcription.
200
Why is gene regulation important?
It ensures that the right genes are expressed at the right times and in the right cells.
200
What is miRNA?
MicroRNAs are small, single-stranded ncRNAs involved in RNA silencing and post-transcriptional gene regulation.
200
Prokaryote gene regulation is typically _______. Eukaryotic gene regulation is typically ________.
[NEEDS TO BE FIXED]
- Prokaryotic gene regulation is typically negative, meaning genes are usually activated unless a regulator inhibits them.
- Eukaryotic gene regulation tends to be positive, with genes usually deactivated unless activated by a regulator.
200
What is in a basic operon?
[NEEDS TO BE FIXED]
Each operon has a single promoter and is controlled by an operator DNA segment, which switches the operon on or off.
200
Binding of an RNA binding protein will ________ the
stability of the RNA molecule.
a. increase
b. decrease
c. neither increase nor decrease
d. either increase or decrease
d. either increase or decrease
[NEEDS TO BE CHECKED]
300
Repressor proteins attach to what part of the enzyme?
Allosteric site
300
What do inducible operons require?
They require an inducer molecule to deactivate the repressor and initiate transcription.
300
Eukaryotic gene expression involves ______ ______ not present in prokaryotic gene expression.
[NEEDS TO BE FIXED]
nonhistone proteins
300
What happens during alternative RNA splicing?
Introns are excised, and exons of the same gene are joined. There is also the addition of a 5' cap and a poly-A-tail at the 3' end occurs.
300
How does a protein get flagged to degrade?
Ubitiquin goes and attaches to the molecule.
400
Control of gene expression in eukaryotic cells occurs at which level(s)?
a. only the transcriptional level
b. epigenetic and transcriptional levels
c. epigenetic and transcriptional and translational levels
d. epigenetic and transcriptional, translational, and post-translational levels
d. epigenetic and transcriptional, translational, and post-translational levels
400
What will result from the binding of a transcription
factor to an enhancer region?
a. decreased transcription of an adjacent gene
b. increased transcription of a distant gene
c. alteration of the translation of an adjacent gene
d. initiation of the recruitment of RNA polymerase
d. initiation of the recruitment of RNA polymerase
400
In the trp operon responsible for tryptophan synthesis, it can be turned off by tryptophan, which acts as a ______ in the negative feedback loop.
corepressor
400
When does negative gene regulation happen?
[NEEDS TO BE CHECKED]
Negative gene regulation happens with repressible and inducible operons, where a repressor protein binding to the operator site inhibits transcription.
400
What are siRNAs:
[NEEDS TO BE FIXED]
Small interfering RNAs constitute a class of double-stranded ncRNAs, typically 20-24 base pairs long.
500
Targeted therapies are used in patients with a set gene
expression pattern. A targeted therapy that prevents the activation of the estrogen receptor in breast cancer would be beneficial to which type of patient?
a. patients who express the EGFR receptor in
normal cells
b. patients with a mutation that inactivates the
estrogen receptor
c. patients with lots of the estrogen receptor
expressed in their tumor
d. patients that have no estrogen receptor expressed
in their tumor
[DOUBLE CHECK]
c. patients with lots of the estrogen receptor
expressed in their tumor
500
The lac operon consists of regulatory regions such as the promoter as well as the structural genes lacZ, lacY, and lacA, which code for proteins involved in lactose metabolism. What would be the outcome of a mutation in one of the structural genes of the lac operon?
a. Mutation in structural genes will stop transcription.
b. Mutated lacY will produce an abnormal β galactosidase protein.
c. Mutated lacA will produce a protein that will transfer an acetyl group to β galactosidase.
d. Transcription will continue but lactose will not be metabolized properly.
d. Transcription will continue but lactose will not be metabolized properly.
[NEEDS TO BE FIXED]
500
The regulator gene produces a _______ _______ that can inhibit operon transcription by binding to the operator.
repressor protein
500
What is an example of an inducible operon?
The lac operon is induced by allolactose, allowing transcription when lactose is present.
500
What chemical process permanently deactivates DNA?
DNA methylation