Study Guide 14 - Winter 2015

Pregunta 1 de 31

1

What would be the likely cellular effects of a large deletion in the gene encoding the polymerase responsible for adding 3′ poly(A) tails to eukaryotic mRNAs?

Selecciona una de las siguientes respuestas posibles:

Inactivation of the polymerase would lead to incomplete pre-mRNA processing, including 3′ end formation, splicing, editing, and transport—and would certainly be lethal.
Activation of the polymerase would lead to incomplete pre-mRNA processing, including 3′ end formation, splicing, editing, and transport—and would certainly be lethal.

Explicación

Pregunta 2 de 31

1

Compare and contrast splicing mechanisms used by spliceosomes, group I introns, and group II introns, with respect to the nucleophiles, proteins, or nucleic acids involved and how the specificity of splice sites is achieved.

Selecciona una de las siguientes respuestas posibles:

Group I and group II introns are generally self-splicing, with only the RNA backbone of the intron required for the reaction in vitro. The nucleophile in the first step, cleavage of the 5′ splice site, is a guanine nucleotide or nucleoside for group I introns, and the 2′-OH of an internal A residue for group II introns. The second step uses the liberated 3′-OH at the 5′ splice site as nucleophile to attack the phosphodiester bond at the 3′ splice site, joining the exons. Site specificity is aided by guide sequences that are part of the intron structures. Introns removed with spliceosomes follow a mechanism similar to group II introns, but also rely on the spliceosome ribonucleoprotein complex to catalyze their excision.
None

Explicación

Pregunta 3 de 31

1

Self-splicing introns do not require an energy source, such as ATP or GTP, to catalyze splicing. How does self-splicing proceed with a reasonable yield of products?

Selecciona una de las siguientes respuestas posibles:

Self-splicing catalyzes phosphodiester exchange reactions with no net loss or gain of energy. Bonds are broken and re-formed with different nucleotides, and there is no change in the number of phosphodiester bonds, just in the covalent bonding partners. Thus, there is no net change in free energy from reactants to products.
none

Explicación

Pregunta 4 de 31

1

Which of the following nuclear pre-mRNA nucleotide sequences potentially contains an intron?

Selecciona una de las siguientes respuestas posibles:

5'--UGACCAUGGCGCUAACACUGCCAAUUGGCCAAUACUGACCUGAUAGCAUCAGCCAA--3'
5'--UAGUCUCAUCUGUCCAUUGACUUCGAAACUGAAUCGUAACUCCUACGUCUAUGGA--3'
5'--UAGCUGUUUGUCAUGACUGACUGGUCACUAUCGUACUAACCUGUCAUGCAAUGUC--3'
5'--UAGCAGUUCUGUCGCCUCGUGGUGCUGGCUGGCCCUUCGUCGCUCGGGCUUAGCUA--3'
5'--UAGGUUCGCAUUGACGUACUUCUGAGACUACUAACUACUAACGCAUCGAGUCUCAA--3'

Explicación

Pregunta 5 de 31

1

One of the five pre-mRNAs shown above is a likely candidate for splicing out an intron sequence. What mRNA nucleotide sequence would one expect to result from this splicing event?

Selecciona una de las siguientes respuestas posibles:

5'--UAGUCUCAA--3'; the putative intron from the 5' GU through the 3' AG has been removed.
none

Explicación

Pregunta 6 de 31

1

Eukaryotic messenger RNA and hnRNA both have ___________ at their 3'-ends.

Selecciona una de las siguientes respuestas posibles:

m7 G caps
poly(A) tails
hairpin structures
covalently bound proteins

Explicación

Pregunta 7 de 31

1

Eukaryotic messenger RNA molecules have _______________ at their 5' ends.

Selecciona una de las siguientes respuestas posibles:

m7 G caps
poly(A) tails
hairpin structures
covalently bound proteins

Explicación

Pregunta 8 de 31

1

Eukaryotes use a variety of pathways to form 5'-m7 G caps.

Selecciona uno de los siguientes:

VERDADERO
FALSO

Explicación

Pregunta 9 de 31

1

The carboxy terminal domain of the largest subunit of RNA polymerase II must be _______________ on Ser-5 to target a transcript for capping.

Selecciona una de las siguientes respuestas posibles:

methylated
phosphorylated
glycosylated
dephosphorylated

Explicación

Pregunta 10 de 31

1

Amino acid-coding regions within eukaryotic genes may be interrupted by ___________ regions.

Selecciona una de las siguientes respuestas posibles:

noncoding
long terminal repeat
split gene
enhancer

Explicación

Pregunta 11 de 31

1

Exons tend to be conserved during evolution, whereas introns usually are not as tightly conserved.

Selecciona uno de los siguientes:

VERDADERO
FALSO

Explicación

Pregunta 12 de 31

1

Two splicing intermediates resemble ______________.

Selecciona una de las siguientes respuestas posibles:

hairpins
projections
lariats
helices

Explicación

Pregunta 13 de 31

1

_______________ permits a cell to recode genetic information in a systematic and regulated fashion.

Selecciona una de las siguientes respuestas posibles:

Replication
Transcription
RNA editing
DNA repair

Explicación

Pregunta 14 de 31

1

Pre-mRNA requires specific sequences for precise __________ to occur.

Selecciona una de las siguientes respuestas posibles:

skipping
splicing
tagging
replication

Explicación

Pregunta 15 de 31

1

A single _____________ can be processed to produce two or more different mRNA molecules.

Selecciona una de las siguientes respuestas posibles:

tRNA
pre-mRNA
snRNP
ribosome

Explicación

Pregunta 16 de 31

1

_________________ assemble to form a spliceosome, the splicing machine that excises introns.

Selecciona una de las siguientes respuestas posibles:

rRNAs
snRNPs
tRNAs
Micro RNAs

Explicación

Pregunta 17 de 31

1

What is the key component of the catalytic site of the spliceosome?

Selecciona una de las siguientes respuestas posibles:

DNA
protein
ribisomes
RNA

Explicación

Pregunta 18 de 31

1

Transcription termination takes place downstream from the _______________

Selecciona una de las siguientes respuestas posibles:

5'-m7 G caps
poly(A) site
promoter region
enhancer sequences

Explicación

Pregunta 19 de 31

1

_________________ molecules can silence gene expression.

Selecciona una de las siguientes respuestas posibles:

Knockout
Short RNA
Spliceosome
Protease

Explicación

Pregunta 20 de 31

1

The ______________ pathway blocks mRNA translation or causes mRNA degradation.

Selecciona una de las siguientes respuestas posibles:

spliceosome
miRNA
ribozyme
snRNP

Explicación

Pregunta 21 de 31

1

Splicing begins as a cotranscriptional process and continues as a posttranscriptional process.

Selecciona uno de los siguientes:

VERDADERO
FALSO

Explicación

Pregunta 22 de 31

1

One form of severe thalassemia is known to be the result of a mutation that causes abnormal RNA splicing because of a five nucleotide deletion that disrupts the first splice donor signal of the beta globin pre-mRNA. All thalassemias result in a reduced rate of synthesis of one of the globin chains (either alpha or beta globin) that make up hemoglobin. Which of the following techniques would best show the presence of the abnormal splicing in a suspected carrier of the disease?

Selecciona una de las siguientes respuestas posibles:

Analysis to detect altered mobility of beta globin protein by electrophoresis
Analysis to detect decreased oxygen binding by red blood cells
Analysis to detect altered size of beta globin protein
Analysis to detect altered DNA sequence of promoter regions
Analysis to detect altered size of beta globin mRNA

Explicación

Pregunta 23 de 31

1

Figure 1 represents regions around a gene encoding a mRNA. Exon I of the mRNA contains the translation initiation AUG codon. Exon IV contains the UGA termination codon. The letters A through E above the diagram refer to areas of the gene and its transcript located directly below them.

Which of the lettered regions of the primary transcript is removed by a spliceosome?

Selecciona una de las siguientes respuestas posibles:

A
B
C
D
E

Explicación

Pregunta 24 de 31

1

Figure 1 represents regions around a gene encoding a mRNA. Exon I of the mRNA contains the translation initiation AUG codon. Exon IV contains the UGA termination codon. The letters A through E above the diagram refer to areas of the gene and its transcript located directly below them.

What region of the DNA contains the TATA box?

Selecciona una de las siguientes respuestas posibles:

A
B
C
D
E

Explicación

Pregunta 25 de 31

1

Figure 1 represents regions around a gene encoding a mRNA. Exon I of the mRNA contains the translation initiation AUG codon. Exon IV contains the UGA termination codon. The letters A through E above the diagram refer to areas of the gene and its transcript located directly below them.

Where is the poly (A) tail added to the transcript?

Selecciona una de las siguientes respuestas posibles:

A
B
C
D
E

Explicación

Pregunta 26 de 31

1

Figure 1 represents regions around a gene encoding a mRNA. Exon I of the mRNA contains the translation initiation AUG codon. Exon IV contains the UGA termination codon. The letters A through E above the diagram refer to areas of the gene and its transcript located directly below them.

Where is the 5' cap added to the transcript?

Selecciona una de las siguientes respuestas posibles:

A
B
C
D
E

Explicación

Pregunta 27 de 31

1

If you used radioactively labeled mRNA produced from the galactose operon (encodes for the galE, galT, and galK genes) as a probe in a southern blot experiment, the mRNA probe would NOT hybridize to which one of following DNA sequences?

Selecciona una de las siguientes respuestas posibles:

The galE gene
The galT gene
The galK gene
The galactose operon P1 or P2 promoters
A bogus question. The mRNA probe would bind to each of the DNA sequences listed above

Explicación

Pregunta 28 de 31

1

RNA interference (RNAi) is regulatory mechanism at the

Selecciona una de las siguientes respuestas posibles:

transcriptional level.
post-transcriptional level.
translational level.
post-translational level.
genomic organization level.

Explicación

Pregunta 29 de 31

1

The trigger for RNA interference (RNAi) is

Selecciona una de las siguientes respuestas posibles:

double stranded DNA
single stranded RNA
double stranded RNA
double stranded RNA to which a single strand RNA is base paired
single stranded RNA with a nick

Explicación

Pregunta 30 de 31

1

You want to clone an insert containing a gene-of-interest into a plasmid vector. Which of the following is TRUE?

Selecciona una de las siguientes respuestas posibles:

Both the insert and plasmid must be cut with the same restriction enzyme
Complementary sticky ends from different DNA molecules cannot base pair
After ligation, the next step is transposition into a bacterial host.
A replication origin is required in both the plasmid and the insert.
More than one of the above statements (A-D) is true

Explicación

Pregunta 31 de 31

1

For the experiment below, cDNA from kidney was labeled green, and cDNA from lung was labeled red. The probes from the two samples were mixed together and hybridized to a microarray, giving the results below. The numbers represent fluorescent intensity for genes AF. Assume that the red and green fluorescent labels give equivalent signal.

kidney lung
green red
gene A 2,000 1,900
gene B 3,000 1,000
gene C 2,000 5,000
gene D 1,500 5,000
gene E 800 1,000
gene F 9,000 10,000

Which gene(s) would you select for study if you were interested in genes required specifically for kidney function?

Selecciona una de las siguientes respuestas posibles:

Genes F and C
Genes F, A, and E
Gene D
Gene C
Gene B

	Creado por John Bench hace más de 9 años

Test sobre Study Guide 14 - Winter 2015, creado por John Bench el 22/03/2015.

Study Guide 14 - Winter 2015

Pregunta 1 de 31

What would be the likely cellular effects of a large deletion in the gene encoding the polymerase responsible for adding 3′ poly(A) tails to eukaryotic mRNAs?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 2 de 31

Compare and contrast splicing mechanisms used by spliceosomes, group I introns, and group II introns, with respect to the nucleophiles, proteins, or nucleic acids involved and how the specificity of splice sites is achieved.

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 3 de 31

Self-splicing introns do not require an energy source, such as ATP or GTP, to catalyze splicing. How does self-splicing proceed with a reasonable yield of products?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 4 de 31

Which of the following nuclear pre-mRNA nucleotide sequences potentially contains an intron?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 5 de 31

One of the five pre-mRNAs shown above is a likely candidate for splicing out an intron sequence. What mRNA nucleotide sequence would one expect to result from this splicing event?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 6 de 31

Eukaryotic messenger RNA and hnRNA both have ___________ at their 3'-ends.

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 7 de 31

Eukaryotic messenger RNA molecules have _______________ at their 5' ends.

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 8 de 31

Eukaryotes use a variety of pathways to form 5'-m7 G caps.

Selecciona uno de los siguientes:

Explicación

Pregunta 9 de 31

The carboxy terminal domain of the largest subunit of RNA polymerase II must be _______________ on Ser-5 to target a transcript for capping.

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 10 de 31

Amino acid-coding regions within eukaryotic genes may be interrupted by ___________ regions.

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 11 de 31

Exons tend to be conserved during evolution, whereas introns usually are not as tightly conserved.

Selecciona uno de los siguientes:

Explicación

Pregunta 12 de 31

Two splicing intermediates resemble ______________.

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 13 de 31

_______________ permits a cell to recode genetic information in a systematic and regulated fashion.

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 14 de 31

Pre-mRNA requires specific sequences for precise __________ to occur.

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 15 de 31

A single _____________ can be processed to produce two or more different mRNA molecules.

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 16 de 31

_________________ assemble to form a spliceosome, the splicing machine that excises introns.

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 17 de 31

What is the key component of the catalytic site of the spliceosome?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 18 de 31

Transcription termination takes place downstream from the _______________

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 19 de 31

_________________ molecules can silence gene expression.

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 20 de 31

The ______________ pathway blocks mRNA translation or causes mRNA degradation.