Study Guide 14 - Winter 2015

Questão 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?

Selecione uma das seguintes:

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.

Explicação

Questão 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.

Selecione uma das seguintes:

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

Explicação

Questão 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?

Selecione uma das seguintes:

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

Explicação

Questão 4 de 31

1

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

Selecione uma das seguintes:

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

Explicação

Questão 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?

Selecione uma das seguintes:

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

Explicação

Questão 6 de 31

1

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

Selecione uma das seguintes:

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

Explicação

Questão 7 de 31

1

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

Selecione uma das seguintes:

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

Explicação

Questão 8 de 31

1

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

Selecione uma das opções:

VERDADEIRO
FALSO

Explicação

Questão 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.

Selecione uma das seguintes:

methylated
phosphorylated
glycosylated
dephosphorylated

Explicação

Questão 10 de 31

1

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

Selecione uma das seguintes:

noncoding
long terminal repeat
split gene
enhancer

Explicação

Questão 11 de 31

1

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

Selecione uma das opções:

VERDADEIRO
FALSO

Explicação

Questão 12 de 31

1

Two splicing intermediates resemble ______________.

Selecione uma das seguintes:

hairpins
projections
lariats
helices

Explicação

Questão 13 de 31

1

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

Selecione uma das seguintes:

Replication
Transcription
RNA editing
DNA repair

Explicação

Questão 14 de 31

1

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

Selecione uma das seguintes:

skipping
splicing
tagging
replication

Explicação

Questão 15 de 31

1

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

Selecione uma das seguintes:

tRNA
pre-mRNA
snRNP
ribosome

Explicação

Questão 16 de 31

1

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

Selecione uma das seguintes:

rRNAs
snRNPs
tRNAs
Micro RNAs

Explicação

Questão 17 de 31

1

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

Selecione uma das seguintes:

DNA
protein
ribisomes
RNA

Explicação

Questão 18 de 31

1

Transcription termination takes place downstream from the _______________

Selecione uma das seguintes:

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

Explicação

Questão 19 de 31

1

_________________ molecules can silence gene expression.

Selecione uma das seguintes:

Knockout
Short RNA
Spliceosome
Protease

Explicação

Questão 20 de 31

1

The ______________ pathway blocks mRNA translation or causes mRNA degradation.

Selecione uma das seguintes:

spliceosome
miRNA
ribozyme
snRNP

Explicação

Questão 21 de 31

1

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

Selecione uma das opções:

VERDADEIRO
FALSO

Explicação

Questão 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?

Selecione uma das seguintes:

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

Explicação

Questão 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?

Selecione uma das seguintes:

A
B
C
D
E

Explicação

Questão 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?

Selecione uma das seguintes:

A
B
C
D
E

Explicação

Questão 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?

Selecione uma das seguintes:

A
B
C
D
E

Explicação

Questão 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?

Selecione uma das seguintes:

A
B
C
D
E

Explicação

Questão 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?

Selecione uma das seguintes:

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

Explicação

Questão 28 de 31

1

RNA interference (RNAi) is regulatory mechanism at the

Selecione uma das seguintes:

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

Explicação

Questão 29 de 31

1

The trigger for RNA interference (RNAi) is

Selecione uma das seguintes:

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

Explicação

Questão 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?

Selecione uma das seguintes:

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

Explicação

Questão 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?

Selecione uma das seguintes:

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

	Criado por John Bench mais de 9 anos atrás

Quiz sobre Study Guide 14 - Winter 2015, criado por John Bench em 22-03-2015.

Study Guide 14 - Winter 2015

Questão 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?

Selecione uma das seguintes:

Explicação

Questão 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.

Selecione uma das seguintes:

Explicação

Questão 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?

Selecione uma das seguintes:

Explicação

Questão 4 de 31

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

Selecione uma das seguintes:

Explicação

Questão 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?

Selecione uma das seguintes:

Explicação

Questão 6 de 31

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

Selecione uma das seguintes:

Explicação

Questão 7 de 31

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

Selecione uma das seguintes:

Explicação

Questão 8 de 31

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

Selecione uma das opções:

Explicação

Questão 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.

Selecione uma das seguintes:

Explicação

Questão 10 de 31

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

Selecione uma das seguintes:

Explicação

Questão 11 de 31

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

Selecione uma das opções:

Explicação

Questão 12 de 31

Two splicing intermediates resemble ______________.

Selecione uma das seguintes:

Explicação

Questão 13 de 31

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

Selecione uma das seguintes:

Explicação

Questão 14 de 31

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

Selecione uma das seguintes:

Explicação

Questão 15 de 31

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

Selecione uma das seguintes:

Explicação

Questão 16 de 31

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

Selecione uma das seguintes:

Explicação

Questão 17 de 31

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

Selecione uma das seguintes:

Explicação

Questão 18 de 31

Transcription termination takes place downstream from the _______________

Selecione uma das seguintes:

Explicação

Questão 19 de 31

_________________ molecules can silence gene expression.

Selecione uma das seguintes:

Explicação

Questão 20 de 31

The ______________ pathway blocks mRNA translation or causes mRNA degradation.