RNA Structure, synthesis and Processing

Question 1

The space between the start codon and the stop codon is called

Answer 1

The open reading frame

Question 2

Transcription is highly selective. True/False

Answer 2

True

Question 3

More than 2% of genome encodes for proteins. True/False

Answer 3

False
(Only 2% encodes for proteins)

Question 4

What is the complete set of RNA transcripts expressed by a genome?

Answer 4

Transcriptome

Question 5

In which part of the cell are microRNA’s found

Answer 5

The cytoplasm

Question 6

What type of RNA makes up 80% of the total RNA in the cell

Answer 6

rRNA

Question 7

RNA with catalytic activity is termed as

Answer 7

Ribozyme

Question 8

Which RNA is the smaller of the three major types of RNA?

Answer 8

tRNA

Question 9

All mRNA’s code for only a single protein and therefore are called

Answer 9

Monocistronic

Question 10

What kind of mRNA is characteristic of prokaryotes

Answer 10

Polycistronic mRNA

Question 11

What kind of mRNA is characteristic of eukaryotes

Answer 11

Monocistronic mRNA

Question 12

An mRNA carrying information from only one gene is

Answer 12

monocistronic

Question 13

An mRNA carrying information from more than one gene is

Answer 13

polycistronic

Question 14

What cap is attached to the 5’ end of mRNA

Answer 14

7-methylguanosine

Question 15

What unusual linkage is between 7-methylguanosine and the 5’ end of the mRNA

Answer 15

5’ to 5’ triphosphate linkage

Question 16

In bacteria, one species of RNA pol synthesizes all of RNA. True or false

Answer 16

True

Question 17

What enzyme synthesizes RNA primers in prokaryotes

Answer 17

Primase

Question 18

Name the two types of enzymes RNA pol is made up of

Answer 18

The core enzyme
The holoenzyme

Question 19

The core enzyme is able to recognize the promoter region and the holoenzyme is not. True/False

Answer 19

False
The holoenzyme is able to recognize the promoter region due to the presence of sigma factor

Question 20

The most important or predominating sigma factor is

Answer 20

Sigma 70

Question 21

What other activity does the sigma factor have apart from recognizing the promoter region

Answer 21

Helicase activity

Question 22

Why is the sigma factor also known as house keeping genes

Answer 22

Because they are essential for the survival of the bacteria

Question 23

Function of DNA topoisomerase

Answer 23

Unwinding of supercoils in DNA

Question 24

In what direction is transcription?

Answer 24

5’ to 3’ direction

Question 25

RNA polymerase does not require a primer. True/False

Answer 25

True

Question 26

RNA polymerase has a 3’ to 5’ exonuclease domain for proofreading. True/False

Answer 26

False RNA polymerase does not have a 3’ to 5’ exonuclease activity

Question 27

The two types of transcription termination in bacteria

Answer 27

a. Rho dependent b. Rho independent

Question 28

What is formed during Rho-independent termination

Answer 28

Hairpin

Question 29

What protein is added to the 5’ end of the nascent RNA during Rho dependent termination?

Answer 29

Rho

Question 30

What drug is efficient in treating tuberculosis?

Answer 30

Rifampincin

Question 31

What makes Rifampincin so efficient?

Answer 31

It prevents chain growth beyond three nucleotides That is, it inhibits transcription

Question 32

Which RNA polymerase is important in transcription in eukaryotes

Answer 32

RNA polymerase 2

Question 33

What general transcription factor recognizes the TATA box in eukaryotic transcription

Answer 33

TFIID ( transcription factor 2 D)

Question 34

What general transcription factor brings the polymerase to the promoter

Answer 34

TFIIF

Question 35

The helicase activity of which general transcription factor melts the DNA to form transcription bubble

Answer 35

TFIIH

Question 36

TFIIH has a kinase activity.True/False

Answer 36

True

Question 37

Which transcriptional factor regulates which genes are expressed at a given point in time

Answer 37

Specific transcriptional factors

Question 38

Variety of motifs through which transcriptional activators or specific transcriptional factors bind to DNA include

Answer 38

Helix-loop-helix Zinc finger Leucine zipper Helix-turn-helix

Question 39

Mutation of Zn finger motif results in what type of Tumor

Answer 39

Wilms Tumor-1

Question 40

What is the role of enhancers in eukaryotic transcription?

Answer 40

They increase the rate of initiation of transcription by RNA pol 2

Question 41

Name the RNA polymerase 2 inhibitor

Answer 41

Alpha- amanitin

Question 42

In the processing of pre-rRNA exons are methylated. True/False

Answer 42

True

Question 43

In tRNA processing, an intron is removed from anticodon loop by

Answer 43

Nucleases

Question 44

In tRNA processing, the 5’ end is trimmed by what ribozyme

Answer 44

RNase P

Question 45

In tRNA processing, the 3’ end is trimmed by which ribozyme?

Answer 45

RNase D

Question 46

In tRNA processing, the addition of the sequence ‘CCA’ at the 3’ end is done by

Answer 46

Nucleotidyltransferase

Question 47

What enzyme adds poly-A tail to the 3’ end?

Answer 47

Polyadenylate [poly(A)] polymerase

Question 48

The process of removing and joining exons is called

Answer 48

Splicing

Question 49

What two sequential transesterifications proceed splicing

Answer 49

lariat formation Exon joining

Question 50

This refers to the different ways of shuffling or joining exons together

Answer 50

Alternative splicing

Question 51

What is the polyadenylation signal sequence prior to the addition of the poly-A tail

Answer 51

AAUAAA

Question 52

In eukaryotes gene expression is also controlled at postrranslational and posttranscriptional processes. True/False

Answer 52

True

Question 53

Enhancer-Activated transcription often requires the presence of a

Answer 53

Coactivator