Transcription and RNA Processing

Question 1

Are the genes that encode the non-major types of RNA translated?

Answer 1

no, they’re not translated but the RNA products producing during transcription used for processing of translation

Question 1

What is the type of eukaryotic RNA polymerase: it is located in the nucleoplasm and synthesizes tRNA, some snRNA, and 5S rRNA?

Answer 1

RNa polymerase III

Question 2

What are the two types of ways transcription is terminated in prokaryotes?

Answer 2

ρ dependent and ρ independent termination

Question 3

What is the general type of enzyme that performs transcription?

Answer 3

DNA dependent RNA polymerase

Question 3

In prokaryotes, the ribosomes bind to what codon in the beginning of translation?

Answer 3

AUG codon

Question 3

What is the purpose for the addition of the 7-methylguanosine cap on the 5’ end of pre-mRNA in the nucleus?(2 points)

Answer 3

It protects the pre-mRNA from degradation and it serves as the attachment site for the ribosomes

Question 4

What protein factor is required for α₂ββ RNA polymerase to initiate transcription at the promotor?

Answer 4

σ factor

Question 5

What is the type of RNA polymerase: it is locaed in the nucleolus and synthesizes 28S, 18S, and 5.8S rRNAs?

Answer 5

RNA polymerase I

Question 5

What is the type of eukaryotic RNA polymerase: it is located in the nucleoplasm and synthesizes hnRNA/mRNA and some snRNA?

Answer 5

RNA polymerase II

Question 5

Eukaryotic RNA polymerases are inhibited by what drugs?(2 points)

Answer 5

α-amantin(RNA polymerase II) and actinomycin D

Question 5

What type of prokaryotic termination of transcription: termination occurs when the newly formed RNA foldsback on itself to form a GC-rich hairpin loop closely followd by 6-8 residues.

Answer 5

ρ-independent

Question 5

What is in the promoter region for RNA polymerase II during transcription of mRNA?(4 points)

Answer 5

Two promoter sequences, TATA box and CAAT box

Question 6

What is a monocistronic message?

Answer 6

mRNA which codes for one protein

Question 7

Polyadenylation of pre-mRNA occurs in what suborganelle structure? This is generally associated with active gene expression in what?

Answer 7

Polyadenylation occurs in the nucelplasm. It is generally associated with gene expression in euchromatin.

Question 8

What is the number system for bases located to the right or downstream from the starting point for transcription?

Answer 8

+2, +3, +4,…

Question 9

What is a transcription factor for RNA polymerase II, assist in initiating transcription?

Answer 9

TFIID

Question 9

Does eukaryotic RNA polymerases require σ factor to initiation transcription at the promoter?

Answer 9

No, they do require TFII to bind before RNA polymerase

Question 9

What is the sequence where an endonuclease cuts the mRNA molecule for the addition of the poly-A tail?

Answer 9

AAUAAA

Question 10

What type of prokaryotic terrmination: termination requires paricipation of protein factor which binds to the newly formed RNA and moves toward the RNA polymerase that has paused at a termination site; protein then displaces RNA plymerase from the 3’ end of the RNA.

Answer 10

ρ dependent termination

Question 11

Why are introns not transcribed to mRNA in the nucleus?

Answer 11

Wrong, both introns and exons are transcribed to mRNA in the nucleus

Question 12

How long does σ factor remain at the promoter during the initiation of transcription?

Answer 12

It is released immediately after the initiation of transcription has taken place

Question 13

What are the major types of processing of pre-mRNA that occur inside the nucleus of a ekaryotic cell?(3 points)

Answer 13

The addition of a 7-methylguanosine to the 5’ end of the mRNA, the addition of the poly-A tail and the removal of the introns from the pre-mRNA

Question 14

A major type of RNA which is used as a structural component of the ribosome to form a complete, functional ribosome?

Answer 14

Ribosomal RNA

Question 15

Ribosome, in prokaryotic translation, synthesized the polypeptide in what direction?

Answer 15

amino terminus to carboxy terminus

Question 16

If the lactose operon conains three different types of gene as part of its coding sequence, how many Shine-Dalgarno sequences at the utranslated region of the mRNA are going to be in the polycistronic mRNA?

Answer 16

three

Question 17

How does RNA polymerase proofread its work?

Answer 17

It doesn't proof its work

Question 17

When/where are introns removed during mRNA transcription eukaryotes?

Answer 17

they're removed during RNA processing in the cytoplasm

Question 18

What part of the tRNA molecule bind to the codon located on mRNA?

Answer 18

the anti-codon region

Question 19

What is another name for TATA box in eukaryotes?

Answer 19

Hogness box

Question 20

What is the specific action of the Shiga toxin from *Shigella dysenteriae* and Verotoxin, shiga-like toxin from enterohemorrhagic *E. coli* on suborganelle structures?**(2 points) **What are the toxins?

Answer 20

It removes the adenine residues from the 28S rRNA found in the 60S subunit. The toxins are RNA glycosylases.

Question 21

The RNA product has what properties when compared to the template strand?**(2 points)**

Answer 21

complementary and anti-parallel

Question 22

How does RNA polymerase recognize the start and end of a particular sequence of bases which encodes a gene?

Answer 22

promotor and terminator

Question 22

What type of RNA polymerase in eukaryotes synthesize mRNA from DNA template strand?

Answer 22

RNA polymerase II

Question 23

What are removed during pre-mRNA processing in eukaryotes: introns or exons?

Answer 23

introns are removed

Question 25

What is the action of rifampin?

Answer 25

Rifampin inhibits prokaryotic RNA polymerase

Question 26

What is the coding segment of mRNA in eukaryotes: introns or exons?

Answer 26

exons

Question 26

How many type of activated amino acids do tRNa molecules carry during translation?

Answer 26

They carry only ONE

Question 28

What is the second most abundant type of RNA in the cell?

Answer 28

tRNA

Question 29

The fist stage in the expression of genetic information is a particular processing of the information to the base sequence of a double-stranded DNA molecule to form the the base sequence of a single-stranded molecule of RNA.

Answer 29

Transcription

Question 31

A major type of RNA which are RNA molecules with enzymatic activity?

Answer 31

ribozyme

Question 32

How does helicase and RNA polymerase work together to seperate the template strand from the coding stand in eukaryotic transcription of mRNA?

Answer 32

RNA polymerase II doesn't work with helicase. RNA polymerase seperates the strands in a short distance and transcribes the mRNA from the 5' to the 3' location and it reads the template strand from the 3' to the 5' direction.

Question 33

When/where are exons are removed in eukaryotes after transcription has taken place?

Answer 33

they're not removed

Question 34

During transcription, does RNA polymerase move in the 5' - 3' direction or the 3' to 5' direction?

Answer 34

It moves in the 3' - 5' direction but it synthesizes from 5' to 3'

Question 34

What are the three basic steps of eukaryotic ribosome synthesis starting from the nucleus?

Answer 34

The eukaryotic rRNA is transcribed by RNA polymerase I in the nucleuolus as one large peice: 45S. The 45S is later broken down into 28S, 5.8S and 18S. RNA polymerase II transcribes the 5S region from a seperate gene. All of the rNA assemble in the nucleolus with ribosomal proteins.

Question 35

What is the purpsoe for the poly-A tail addition to the 3' end of the pre-mRNA molecule in eukaryotic processing of mRNA?

Answer 35

Protects the pre-mRNA from degradation from nucleases and it aids it transport to the cytoplasm

Question 36

All transcription can be inhibited by what drug?

Answer 36

antinomycin D

Question 36

What portion of the tRNA molecule is phosphorylated?

Answer 36

The 5' end

Question 37

What type of primer is required for transcription?

Answer 37

None

Question 38

What is the rRNA that make up the 30S subunit?

Answer 38

16S RNA

Question 39

A major type of RNA that is found only in the nucleus of eukaryotes but one of its major function is to participate int he splicing of eukaryotes?

Answer 39

small nuclear RNA

Question 40

What specific sequences are required at hte promoter location for prokaryotic transcrition?**(4 points)**

Answer 40

2 promoter sequences, a "TATA" box and a -35 sequence

Question 41

The ρ-independent termination mechanism in prokaryotic transcription has a base sequence rich in what specific type of nucleotides?**(2 points)**

Answer 41

Guanine/Cytosine base pairing mechanism

Question 42

When does translation start in prokaryotes?

Answer 42

Translation and transcription occur at the same time in prokaryotes

Question 44

What is the most abundant type of RNA in the cell?

Answer 44

ribosomal RNA

Question 45

What is the coding seqeunce of the acceptor arm that careries the amino acid in a tRNA molecule?

Answer 45

5'-CCA-3'

Question 46

What is a polycistronic message?

Answer 46

mRNA which codes for multiple proteins

Question 47

What is the purpose of the poly-A tail in eukaryotic processing of pre-mRNA?**(2 points)**

Answer 47

protects the mRNA from degradation and transportation to the cytoplasm

Question 49

What is the single prokaryotic RNA polymerase that synthesizes all types of RNA in the cell?

Answer 49

α₂ββ'

Question 50

How are the introns removed and exons assembled in pre-mRNA processing in eukaryotes?**(3 points)**

Answer 50

Introns are removed by splicosomes, i.e., snRNP, from the 5'(donor) to the 3'(acceptor) ends of the intron. The introns are removed. The intron is excised in the form of a lariat structure and later degraded. The neighboring exons are joined together to join the coding region of mRNA.

Question 52

What are the major roles of RNA in the cell?(6 points)

Answer 52

tRNA, ribosomal RNA, messenger RNA, heterogenerous nuclear RNA, small nuclear RNA and ribozymes

Question 53

What is the rRNA that make up the 60S subunit?**(3 points)**

Answer 53

5S, 5.8S and 28S rRNA

Question 55

Where does RNA polymerase bind to begin transcription?

Answer 55

promoter region

Question 56

What are the two subunits of rRNA that make up the eukaryotic ribosome?

Answer 56

40S and 60S

Question 58

Where do the ribosomes bind on the prokaryotic mRNA to initiate translation?

Answer 58

Shine Dalgarno region on the untranslated region of the mRNA. This is the 5' region of the UTR region.

Question 59

All of the intermediate pre-mRNA structures in the pre-mRNA procesing which occurs in eukaryotes, are referred to as what?

Answer 59

hnRNA or heterogenous nucleus RNA

Question 60

What type of introns are found in prokaryotes?

Answer 60

none

Question 63

In prokaryotes, how does helicase work together with RNA polymerase to seperate the template strand from the non-template(coding) strand?

Answer 63

RNA polymerase the two strands as it reads the base sequence of the templerate strand

Question 64

What is the action of actinomycin D?

Answer 64

It binds to the DNA and preventing transcription

Question 65

What is the rRNA that make up the 50S subunit?(2 points)

Answer 65

5S and 23S

Question 67

When does transcription end?

Answer 67

When RNA reaches a termination signal

Question 68

What specitic type of sequences are found in the termination signal are found during eukaryotic transcription?

Answer 68

It is a terminal signal that isn't well understood

Question 69

A major type of RNA which carries the information specifying the amino acid sequence of a protein to the ribosome?

Answer 69

Messenger RNA

Question 70

What type of RNA polymerase in eukaryotes synthesize the eukaryotic ribosome?**(2 points)**

Answer 70

RNA polymerase I and RNA polymerase II. RNA polymerase I synthesizes a large portion of the rRNA that makes up the ribosome

Question 72

What is the number system for bases locatd to the left or upstream from the starting point for transcription?

Answer 72

-1,-2,-3,...

Question 73

A major type of RNA that is found only in the nucleus of eukaryotic cells?

Answer 73

heterogeneous nuclear RNA

Question 74

What is the rNA that make up the 40S subunit?

Answer 74

18S rRNA

Question 75

What RNA polymerase transcribes tRNA in eukaryotes?

Answer 75

RNA polymerase III

Question 76

What is an example of mRNA that doesn't have a poly-A tail?

Answer 76

histone mRNA molecules

Question 77

During translation, what is the polarity of the synthesis of the polypeptide product?

Answer 77

Amino end to the carboxy terminus

Question 78

What are the non-coding segments of mRNA?

Answer 78

introns

Question 79

What is another name for "TATA" box required in the bacterial promotor for transcription to take place?

Answer 79

Prinbow box

Question 80

Are eukaryotic mRNA molceuls monocistronic, polycistronic or both?

Answer 80

monocistronic

Question 82

What is a toxin from certain mushrooms that inhibt RNA polymerase II?

Answer 82

α-amanitin

Question 84

What protein factor is sometimes required for the termination of transcription?

Answer 84

ρ factor

Question 85

What is an example of alternative splicing of eukaryotic primary pre-mRNA transcripts?**(2 points)**

Answer 85

The synthesis of the muscle proteins troponin T and tropomysin go through alternative splicing. Also, the surface immunoglobulins of unstimulated B cells go through alternative splicing

Question 86

The activated amino acid is attached to what portion of the tRNA molecule?

Answer 86

The 3' OH portion of the tRNA molecule

Question 87

What are the two subunits that makes up prokaryotic ribosome?

Answer 87

30S and 50S

Question 88

What type of mutation is known to cause β-thalassemia?

Answer 88

a mutation in the splice site of the β-thalassemia protein

Question 89

Do Eukaryotic RNA polymerase require a protein factor to terminate transcription?

Answer 89

No

Question 90

When it comes to the numbering system for a gene, the first base transcribed as RNA is efined as what?

Answer 90

The +1 base of that gene region

Question 91

During transcription, is the RNA product parallel or antiparallel to the template DNA strand?

Answer 91

anti-parallel

Question 92

Ribosomes translated the message in what direction of the mRNA?

Answer 92

5' to 3' direction