A functioning unit of DNA which contains a cluster of several
structural genes that are regulated by a common operator under a
common promoter is called an operon. All of the genes in an operon
are transcribed together.
In prokaryotes, the transcribed mRNA remains as polycistronic mRNA.
In eukaryotes,, by splicing monocistronic mRNAs are formed. These
monocistronic mRNAs get translated separately.
Hence, option E is the correct answer.
What is an operon? Choose one: A. a short sequence of DNA to which a transcription...
The diagram below illustrates the LAC operon in its OFF state when the inducer molecule —lactose—is absent. Predict the ways in which the following conditions will affect the transcription of the lactose-utilization genes. OPERON Regulatory Promoter Operator_ gene Lactose-utilization genes DNA mRNA RNA polymerase cannot attach to promoter Active repressor Protein If a mutation in the regulatory gene results in a misfolding of the repressor protein so that it can no longer bind DNA, the lactose-utilization genes O Will be...
8. In transcription, A) mRNA is synthesized from DNA B) the starting point of synthesis is the promoter site C) RNA polymerase binds to the promoter during initiation D) the ending point of synthesis is the terminator site E) All of the above The tryptophan (trp) operon is actively transcribed (i.e. gene expression occurs) A) when there is excess tryptophan in the cell. B) when there is a lack of tryptophan in the cell. C) constitutively because the trp operon...
Match each term associated with genes and control of gene expression with the appropriate description. A transcriptional unit" that consists of promoter multiple genes under the control of a single regulatory element. A transcriptional regulatory protein (prokaryotic or eukaryotic) which works by turning on or increasing gene transcription. activator The region of a gene to which RNA polymerase binds. Enhancer A transcriptional regulatory protein prokaryotic or eukaryotic) which works by turning off or decreasing gene transcription. repressor A molecule that...
There are several possible mutations in the trp operon:
trpP -is a mutation in the promoter sequence
that prevents RNA polymerase from binding to the promoter and
initiate transcription of the trp operon genes.
trpOcis a mutation in the operator sequence
that prevents the trp repressor protein from binding to
the operator to block transcription of the trp operon
genes.
trpR-is a mutation in the repressor protein
that either prevents repressor protein from being made or produces
a mutant repressor...
Question 1 Match the term with the best definition or description; most topics relate to the regulation of gene expression. General type of protein which will increase transcription rates when it attaches to a site A. Factor connected to a particular gene - B. Co-repressor C. Enhancer D. Promoter E. Structural F. Intron G. Activator H. Operator I. Basal transcription J. Glucocorticoid receptor K. Sigma factor L. Mediator M. Inducer N. TATA box O. Repressor The rates of mRNA produced...
for
1-5 define those
The Lac operon is an inducible set of genes found in bacteria cells that helps the bacteria to metabolize the disaccharide lactose. When it is turned on it produces proteins that pump lactose into the bacteria cell and break it down into glucose and galactose, which can then be used by the bacteria as a source of energy The two figures below show the Lac Operon along with the lacl gene (which regulates the Lac operon...
A) An Operon is:? 1- A gene that affect another gene transcription. 2. A gene coding for a metabolic pathway. 3. A protein that blockgene expression. 4. A set of genes under the control of one promoter. B )- In bacteria the Lac Operon genes code for proteins that break down.? 1- Arabinose 2- Lactose 3- Galactose 4- Glucose C )mRNA processing involves removal of .......? 1- Introns 2- The poly-A tail 3- The 5' cap 4- Exons D )...
In rho-dependent transcription termination: the formation of a hairpin in the transcribed mRNA causes RNA polymerase to pause, facilitating termination. rho binds the mRNA, and when it makes contact with RNA polymerase, it assists with the removal of the mRNA from the DNA template. the rho factor binds to the -10 consensus sequence located in the promoter region to terminate transcription. a site within the poly(A) tail is cleaved which signals termination. the 3' untranslated region (3" UTR) is synthesized....
Which of the following statements is correct concerning operon gene control? Positive control requires an activator protein to stimulate transcription of the structural genes within an operon. In negative control, a repressor protein inhibits or turns off transcription of the structural genes within the operon. An inducible operon normally is not transcribed. It requires an inducer molecule to stimulate transcription either by inactivating a repressor protein in a negative inducible operon or by stimulating the activator protein in a positive...
Yet, all the cells in your body contain the same
genes (and same alleles). The difference across cell types
is that genes get selectively expressed (turned on or off)
based on the proteins needed for cellular function given their
environment.
Select which statement explains the reason why hair does not
normally grow on your muscle cells.
a.
Muscle cells have the gene for keratin, but do not express
it
b.
Muscle cells do not have the gene for keratin and...