Deck 5: Gene Expression: Transcription

Question 1

Which of the following catalyzes the synthesis of ribosomal RNA in eukaryotes?

A)RNA polymerase I
B)RNA polymerase II
C)RNA polymerase III
D)Both RNA polymerase I and II
E)Both RNA polymerase I and III

Answer 1

E

Question 2

Sequences that contain information about the stability of a transcript are found in the

A)5' UTR.
B)coding sequence.
C)3' UTR.
D)leading strand.
E)lagging strand.

Answer 2

C

Question 3

During the initiation step of transcription,which molecule binds the promoter region of a DNA molecule?

A)DNA polymerase
B)Reverse transcriptase
C)RNA polymerase
D)DNA primase
E)Topoisomerase

Answer 3

C

Question 4

The process by which genetic information is transferred from DNA to RNA is called

A)replication.
B)transcription.
C)translation.
D)transversion.
E)transformation.

Question 5

Which type of RNA is found only in eukaryotes?

A)mRNA
B)tRNA
C)rRNA
D)snRNA
E)All of these

Question 6

Which of the following is not found in a eukaryotic promoter?

A)-10 box
B)TATA box
C)GC box
D)CAAT box
E)None of these

Question 7

In eukaryotes,where does transcription take place?

A)In the cytoplasm
B)Anywhere in the cell
C)In the nucleus
D)In both the cytoplasm and nucleus
E)In the mitochondria

Question 8

In eukaryotes,precursor mRNA molecules are processed in the

A)ribosomes.
B)nucleus.
C)mitochondria.
D)cytoplasm.
E)nucleolus.

Question 9

In eukaryotes,the initiation complex binds DNA at the

A)Pribnow box.
B)GC box.
C)CAAT box.
D)TATA box.
E)GTF region.

Question 10

A prokaryotic mRNA transcript is

A)transcribed completely before being translated.
B)further processed before it is transcribed.
C)transported from the nucleus before it is translated.
D)modified before it is translated.
E)translated as it is being transcribed.

Question 11

Prokaryotic transcription begins when RNA polymerase binds to which site of the gene region?

A)-35
B)-10
C)+1
D)+10
E)+35

Question 12

Posttranscriptional insertion or deletion of nucleotides that is absent in the DNA template is called

A)RNA splicing.
B)RNA editing.
C)RNA processing.
D)RNA capping.
E)RNA modification.

Question 13

The poly(A)tail of an mRNA

A)helps transport the pre-mRNA to the cytoplasm.
B)keeps the coding sequences from being degraded.
C)is added without an RNA template.
D)is important in initiation of translation.
E)is removed from an mRNA after its maturation.

Question 14

Molecules of tRNA are

A)75 to 90 nucleotides in length.
B)single-stranded with secondary structure.
C)cloverleaf in shape.
D)synthesized with modified bases.
E)All of these

Question 15

The single strand of mRNA that is produced during transcription has the same polarity as the ________ strand of DNA.

A)template
B)nontemplate
C)leading
D)lagging
E)nonsense

Question 16

During transcription,the synthesis of the mRNA strand proceeds in which direction?

A)5' to 3' only
B)3' to 5' only
C)Both 5' to 3' and 3' to 5'
D)Either 5' to 3' or 3' to 5'
E)First 5' to 3',and then 3' to 5'

Question 17

Self-cleaving RNAs that function catalytically are called

A)snRNPs.
B)snRNAs.
C)ribozymes.
D)ribosomes.
E)spliceosomes.

Question 18

Which parts of a eukaryotic gene are transcribed?

A)Only the exons
B)Only the introns
C)Both the exons and introns
D)Exons,introns,promoter,and terminator sequence
E)It depends on the gene

Question 19

Which of the following proteins is found only in the RNA polymerase holoenzyme?

A)Alpha
B)Beta
C)Epsilon
D)Sigma
E)Rho

Question 20

RNA polymerase has no proofreading activity during transcription.

Question 21

What is the difference between an intervening sequence and an untranslated region in a eukaryotic mRNA?

Question 22

Group I introns,such as those found in Tetrahymena,are unique in that they are excised from mRNA by a protein-driven catalytic reaction.

Question 23

Termination is carried out by RNA polymerase in a rho-independent terminator.

Question 24

All genes encode proteins.

Question 25

Activators are cis-acting sequences that increase transcription from a promoter.

Question 26

What kind of experiment or analysis could you conduct to define the location of the promoter elements of protein-coding genes?

Question 27

A rho-dependent terminator

A)forms a hairpin loop during termination.
B)requires ATP to complete termination.
C)is rich in AT nucleotides.
D)Both A and B
E)All of these

Question 28

The number of initiations of transcription from a promoter that has the sequence 5'-TAGCAT-3' will be greater than the number of initiations from a wild-type promoter.

Question 29

The Rho protein is a topoisomerase that helps in untwisting the DNA template.

Question 30

Before a prokaryotic mRNA can be translated,it must be modified by the addition of a polyA tail.

Question 31

What is the function of the inverted repeat in the termination sequence of a rho-independent terminator? What would happen if a mutation occurred in this region?

Question 32

A promoter is a coding portion of a gene.

Question 33

What was the significance of the 1978 finding by Philip Leder's research group that the 0.7 kb β-globin mRNA is not colinear with the gene that encodes it,but the nuclear 1.5 kb pre-mRNA is?

Question 34

What would be the advantage of having multiple sigma factors that each could be produced under different stress conditions in E.coli?

Question 35

Unlike eukaryotic mRNA,prokaryotic mRNA is polycistronic.

Question 36

What are the three basic steps of transcription?

Question 37

The sequence of a template strand of DNA is 3'-CATTACGCTT-5'.What is the sequence of the corresponding mRNA?

Question 38

What are the three regions of a prokaryotic gene?

Question 39

Outline the basic differences in function among RNA polymerases in both prokaryotes and eukaryotes.

Question 40

In eukaryotes,what is the difference between promoter proximal elements in "housekeeping genes" vs.cell-specific genes,and how does this relate to gene expression?

Question 41

How does the rate of initiation of transcription relate to the similarity of the promoter region to the consensus sequence?

Question 42

Describe the structure and organization of the rDNA repeat unit in eukaryotes.

Question 43

What are the functions of the 5' cap and poly(A)tail of mature mRNAs in eukaryotes?

Question 44

Cite at least three ways in which transcription differs from DNA replication.

Question 45

What is the advantage of having a promoter sequence upstream of a coding sequence?