Question 1

The precursors of most eukaryotic rRNAs are synthesized by
I.RNA polymerase I.
II.RNA polymerase II.
III.RNA polymerase III.
A)I or III
B)I or II
C)I only
D)II only
E)III only

Accepted Answer

Most eukaryotic rRNAs are transcribed by RNA polymerase I, therefore the precursor rRNAs are synthesized by RNA polymerase I only. RNA polymerase II transcribes mRNA and some non-coding RNAs, while RNA polymerase III transcribes tRNA and some other non-coding RNAs.

Question 2

The fact that some eukaryotic rRNAs are self-splicing indicates that
A)RNA structures are highly variable.
B)RNAs can contain modified bases.
C)eukaryotes have multiple RNA polymerases.
D)RNA can act as an enzyme or catalyst.
E)None of the above is correct.

Accepted Answer

E

Question 3

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-Eukaryotic RNA molecules are altered by removal of intervening sequences called ______.
A)Rho (Þ)
B)introns
C)sigma (σ)
D)sense
E)operons
F)structural
G)Pribnow
H)promoters
I)antisense
J)exons
K)nucleolus
L)TATA
M)Sense
N)AAAA (poly A)
O)Ribosome

Accepted Answer

Eukaryotic RNA molecules are altered by the removal of intervening sequences called introns.

Answer: J
 The non-intervening sequences in eukaryotic RNA molecules are called exons.

Question 4

Imagine that a new drug is proposed which is hypothesized to selectively bind the transcription factor TBP.Which of the following would be affected?
I.RNA polymerase I
II.RNA polymerase II
III.RNA polymerase III
IV.E.coli RNA polymerase
A)(F1F1F1S1F1F1F10F1F1F1S1F1F1F10F1F1F1S1F1F1F10F1F1F1S1F1F1F10F1F1F1S1F1F1F10F1F1F1S1F1F1F10F1F1F1S1F1F1F10F1F1F1S1F1F1F10F1F1F1S1F1F1F10F1F1F1S1F1F1F10F1F1F1S1F1F1F10F1F1F1S1F1F1F10F1F1F1S1F1F1F10V)
B)I, II, III
C)I only
D)II only
E)IV only

Accepted Answer

TBP (TATA-binding protein) is a component of the transcription factor TFIID, which is involved in the initiation of transcription by RNA polymerase I, II, and III in eukaryotes. E. coli RNA polymerase does not use TBP.

Question 5

The precursors of eukaryotic mRNAs are synthesized by ______.
I.RNA polymerase I.
II.RNA polymerase II.
III.RNA polymerase III.
A)I or III
B)I or II
C)I only
D)II only
E)III only

Accepted Answer

Precursors of eukaryotic mRNAs are synthesized by RNA polymerase II. RNA polymerase I is responsible for transcription of rRNA and RNA polymerase III is responsible for transcription of tRNA and other small RNA molecules.

Question 6

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-Protein-coding genes are also known as ______ genes.
A)Rho (Þ)
B)introns
C)sigma (σ)
D)sense
E)operons
F)structural
G)Pribnow
H)promoters
I)antisense
J)exons
K)nucleolus
L)TATA
M)Sense
N)AAAA (poly A)
O)Ribosome

Accepted Answer

Protein-coding genes are also known as structural genes.

Question 7

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-CpG islands function analogously to prokaryotic ______.
A)Rho (Þ)
B)introns
C)sigma (σ)
D)sense
E)operons
F)structural
G)Pribnow
H)promoters
I)antisense
J)exons
K)nucleolus
L)TATA
M)Sense
N)AAAA (poly A)
O)Ribosome

Accepted Answer

CpG islands are regions of DNA that are rich in CpG dinucleotides and often found near or within gene promoters. They function to recruit transcription factors and RNA polymerase to initiate transcription. Promoters are regions of DNA that signal the start of transcription and bind proteins such as transcription factors, allowing RNA polymerase to bind and initiate transcription.

Question 8

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-Termination of bacterial transcription requires the ______ factor.
A)Rho (Þ)
B)introns
C)sigma (σ)
D)sense
E)operons
F)structural
G)Pribnow
H)promoters
I)antisense
J)exons
K)nucleolus
L)TATA
M)Sense
N)AAAA (poly A)
O)Ribosome

Accepted Answer

Termination of bacterial transcription requires the Rho factor.

Question 9

Most ______ have well defined 3F1F1F1S1F1F1F10 ends terminating in poly(A)tails of ~ 250 nt.
A)prokaryotic mRNAs
B)eukaryotic mRNAs
C)prokaryotic rRNAs
D)eukaryotic rRNAs
E)all of the above

Accepted Answer

Eukaryotic mRNAs have well defined 3' and 5' ends terminating in poly(A)tails of ~ 250 nt, while prokaryotic mRNAs have a Shine-Dalgarno sequence near the 5' end and often lack poly(A) tails. Prokaryotic and eukaryotic rRNAs do not have poly(A) tails as they are not translated into proteins.

Question 10

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-Prokaryotic contain nucleotide sequences know as _____ which contain related genes with related functions.
A)Rho (Þ)
B)introns
C)sigma (σ)
D)sense
E)operons
F)structural
G)Pribnow
H)promoters
I)antisense
J)exons
K)nucleolus
L)TATA
M)Sense
N)AAAA (poly A)
O)Ribosome

Accepted Answer

Prokaryotic cells contain operons, which are nucleotide sequences containing related genes with related functions.

Question 11

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-The DNA strand that serves as a template during transcription is known as the ______ or noncoding strand.
A)Rho (Þ)
B)introns
C)sigma (σ)
D)sense
E)operons
F)structural
G)Pribnow
H)promoters
I)antisense
J)exons
K)nucleolus
L)TATA
M)Sense
N)AAAA (poly A)
O)Ribosome

Accepted Answer

The DNA strand that serves as a template during transcription is called the antisense or noncoding strand.

Question 12

The term rRNA refers to ______ RNA.
A)ribosomal
B)retroviral
C)recombinant
D)rho factor

Accepted Answer

rRNA stands for ribosomal RNA, which is an essential component of ribosomes and plays a crucial role in protein synthesis. It is the most abundant type of RNA in cells. Retroviral RNA (B) is found in retroviruses, recombinant RNA (C) is a term used to describe RNA molecules that have been artificially modified to contain genetic material from different sources, and rho factor (D) is a bacterial protein involved in transcription termination.

Question 13

In prokaryotes, the _____ factor recognizes base sequences in the _____ which facilitates RNA polymerase binding and initiates RNA synthesis.
A)(F1F1F1S1F1F1F10; promoter)
B)regulatory; enhancer
C)(F1F1F1S1F1F1F10; enhancer)
D)regulatory; promoter
E)omega; promoter

Accepted Answer

In prokaryotes, the sigma factor (σ) recognizes specific base sequences in the promoter region of DNA, facilitating the binding of RNA polymerase and initiation of transcription. The answer option A correctly identifies the sigma factor and promoter as the factors involved in RNA synthesis. The other options incorrectly identify regulatory factors and enhancers, which are found in eukaryotes, not prokaryotes. The omega factor is not involved in transcription initiation in prokaryotes.

Question 14

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-An AT-rich region found in eukaryotic promoters is called the ______ box.
A)Rho (Þ)
B)introns
C)sigma (σ)
D)sense
E)operons
F)structural
G)Pribnow
H)promoters
I)antisense
J)exons
K)nucleolus
L)TATA
M)Sense
N)AAAA (poly A)
O)Ribosome

Accepted Answer

The TATA box is the AT-rich region found in eukaryotic promoters.

Question 15

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-The expressed sequences of eukaryotic pre-mRNAs are known as ______.
A)Rho (Þ)
B)introns
C)sigma (σ)
D)sense
E)operons
F)structural
G)Pribnow
H)promoters
I)antisense
J)exons
K)nucleolus
L)TATA
M)Sense
N)AAAA (poly A)
O)Ribosome

Accepted Answer

Exons are the expressed sequences of eukaryotic pre-mRNAs.

Answer: B
 Introns are non-coding sequences that interrupt the expressed sequences (exons) of eukaryotic pre-mRNAs.

Answer: H
 Promoters are DNA sequences that initiate transcription of mRNA.

Answer: N
 AAAA (poly A) is a sequence of adenine nucleotides that is added to the 3' end of eukaryotic mRNA.

Answer: K
 The nucleolus is a substructure of the nucleus where ribosomal RNA is synthesized and ribosomes are assembled.

Question 16

Transcriptional activators that can have variable positions and orientations are called
A)core promoter elements.
B)upstream promoter elements.
C)CpG islands.
D)enhancers.
E)Inr elements.

Accepted Answer

Enhancers are transcriptional activators that can be located at varying distances from the promoter and can have variable orientations. Core promoter elements (A) are found at the transcription start site and are necessary for the initiation of transcription. Upstream promoter elements (B) are located upstream of the core promoter and typically bind to transcription factors to assist in the initiation of transcription. CpG islands (C) are regions of DNA that contain many cytosine and guanine bases and are often associated with the promoter region of a gene, but they are not transcriptional activators themselves. Inr elements (E) are short sequences found at the start of some promoters that are involved in the recognition of the transcription start site.

Question 17

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-In eukaryotes, RNA polymerase does not include a removable ______ factor.
A)Rho (Þ)
B)introns
C)sigma (σ)
D)sense
E)operons
F)structural
G)Pribnow
H)promoters
I)antisense
J)exons
K)nucleolus
L)TATA
M)Sense
N)AAAA (poly A)
O)Ribosome

Accepted Answer

Sigma factor is only found in prokaryotes and is responsible for recognizing the promoter region and initiating transcription. Eukaryotes have different transcription factors that recognize promoters and initiate transcription, but they do not include a removable sigma factor.

Answer: B, G, H, J, K, L, N
 These are all components involved in eukaryotic transcription. B, introns, are non-coding regions that are spliced out of the pre-mRNA before translation. G, Pribnow box, and L, TATA box, are regions in the promoter sequence that help recruit the transcription machinery. H, promoters, are DNA sequences that promote the initiation of transcription. J, exons, are coding regions that are spliced together after introns are removed to form the final mRNA molecule. K, nucleolus, is a structure within the nucleus where ribosomal RNA is synthesized. N, poly A tail, is added to the 3' end of mRNA and helps stabilize the molecule and facilitate export from the nucleus.

Question 18

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-Eukaryotic rRNA genes are transcribed and processed in the ______.
A)Rho (Þ)
B)introns
C)sigma (σ)
D)sense
E)operons
F)structural
G)Pribnow
H)promoters
I)antisense
J)exons
K)nucleolus
L)TATA
M)Sense
N)AAAA (poly A)
O)Ribosome

Accepted Answer

Eukaryotic rRNA genes are transcribed and processed in the nucleolus.

Question 19

All cellular RNAs are transcribed from
A)DNA templates.
B)RNA templates.
C)either DNA or RNA templates, but not both in the same organism.
D)a combination of DNA and RNA templates.
E)none of the above

Accepted Answer

RNA is transcribed from DNA templates through the process of transcription. This is a fundamental process that occurs in all cellular organisms. RNA does not serve as a template for the synthesis of other RNAs in living cells. Therefore, the correct option is A.

Question 20

The precursors of 5S rRNA, the tRNAs, and a variety of other small nuclear and cytosolic RNAs are synthesized by ______.
I.RNA polymerase I.
II.RNA polymerase II.
III.RNA polymerase III.
A)I or III
B)I or II
C)I only
D)II only
E)III only

Accepted Answer

Small nuclear and cytosolic RNAs as well as tRNAs are synthesized by RNA polymerase III. While 5S rRNA is synthesized by RNA polymerase I. RNA polymerase II is responsible for the transcription of protein-coding genes. Therefore, the correct answer is III only.

Quiz 26: Transcription and Rna Processing

The precursors of most eukaryotic rRNAs are synthesized by I.RNA polymerase I. II.RNA polymerase II. III.RNA polymerase III.

The fact that some eukaryotic rRNAs are self-splicing indicates that

Matching Choose the correct answer from the list. Not all the answers will be used. -Eukaryotic RNA molecules are altered by removal of intervening sequences called ______.

Imagine that a new drug is proposed which is hypothesized to selectively bind the transcription factor TBP.Which of the following would be affected? I.RNA polymerase I II.RNA polymerase II III.RNA polymerase III IV.E.coli RNA polymerase

The precursors of eukaryotic mRNAs are synthesized by ______. I.RNA polymerase I. II.RNA polymerase II. III.RNA polymerase III.

Matching Choose the correct answer from the list. Not all the answers will be used. -Protein-coding genes are also known as ______ genes.

Matching Choose the correct answer from the list. Not all the answers will be used. -CpG islands function analogously to prokaryotic ______.

Matching Choose the correct answer from the list. Not all the answers will be used. -Termination of bacterial transcription requires the ______ factor.

Most ______ have well defined 3 ends terminating in poly(A) tails of ~ 250 nt.

Matching Choose the correct answer from the list. Not all the answers will be used. -Prokaryotic contain nucleotide sequences know as _____ which contain related genes with related functions.

Matching Choose the correct answer from the list. Not all the answers will be used. -The DNA strand that serves as a template during transcription is known as the ______ or noncoding strand.

The term rRNA refers to ______ RNA.

In prokaryotes, the _ factor recognizes base sequences in the _ which facilitates RNA polymerase binding and initiates RNA synthesis.

Matching Choose the correct answer from the list. Not all the answers will be used. -An AT-rich region found in eukaryotic promoters is called the ______ box.

Matching Choose the correct answer from the list. Not all the answers will be used. -The expressed sequences of eukaryotic pre-mRNAs are known as ______.

Transcriptional activators that can have variable positions and orientations are called

Matching Choose the correct answer from the list. Not all the answers will be used. -In eukaryotes, RNA polymerase does not include a removable ______ factor.

Matching Choose the correct answer from the list. Not all the answers will be used. -Eukaryotic rRNA genes are transcribed and processed in the ______.

All cellular RNAs are transcribed from

The precursors of 5S rRNA, the tRNAs, and a variety of other small nuclear and cytosolic RNAs are synthesized by ______. I.RNA polymerase I. II.RNA polymerase II. III.RNA polymerase III.