Transcription

Question 1

what is the one gene one enzyme hypothesis

Answer 1

a single gene codes for one enzyme

Question 2

DNa dependent synthesis of RNA or the use of DNA as a template to synthesize RNA

Answer 2

transcription

Question 3

percent of genes in prokaryotes

Answer 3

3-30%

Question 4

percent of genes in eukaryotes

Answer 4

1-10%

Question 5

a sequence of 20-200 bases “upstream” from a gene that serves as a recognition site for binding RNA polymerase

Answer 5

promoter

Question 6

promoter contains these regions that identify the region as a promoter

Answer 6

consensus sequeces

Question 7

where are the consensus sequences located

Answer 7

-35 and -10 nucleotides from the promoter

Question 8

the promoter occurs on the ____ strand

Answer 8

nontemplate

Question 9

the enzyme that “reads” DNA to synthesize RNA

Answer 9

RNA polymerase

Question 10

core enzyme of RNA polymerase

Answer 10

two alphas
beta
beta prime
omega

Question 11

subunit for DNA binding

Answer 11

beta prime

Question 12

subunit for the catalytic site

Answer 12

beta

Question 13

subunit that deals with promoter binding, assembly and regulation

Answer 13

alpha

Question 14

subunit that deals with structural role, restores activity

Answer 14

omega

Question 15

promoter recognition that transiently bind to core enzyme to allow binding to correct strand and initiation site

Answer 15

sigma factor

Question 16

three stages of transcription

Answer 16

initiation
elongation
termination

Question 17

RNA polymerase binds to promoter causing _____ and _____

Answer 17

strand separation and unwinding

Question 18

Initiation is complete after

Answer 18

about 10 NTPs have been added

Question 19

what continues as the sigma factor falls away

Answer 19

elongation

Question 20

An ATP dependent helicase that catalyzes the unwinding of RNA:DNA duplex hybrids during transcription to promote termination of prokaryotic transcription

Answer 20

Rho factor

Question 21

terminator makes this structure in prokaryotes

Answer 21

hairpin structures

Question 22

five points about eukaryotic transcription

Answer 22

1. three different RNA polymerase that cannot initiate transcription
2. promoters are more complex that consensus sequences
3. initiation requires many transcription factors to activate RNA polymerase
4. regulatory elements modify gene expression
5. transcripts require considerable processing prior to translation

Question 23

location and function of RNA polymerase I in eukaryotes

Answer 23

located in nucleolus

transcribes large rRNAs

Question 24

location and function of RNA polymerase II in eukaryotes

Answer 24

located in nucleus

transcribes mRNAs and snRNAs

Question 25

location and function of RNA polymerase III in eukaryotes

Answer 25

located in the nucleus | transcribes tRNAs and 5s rRNAs

Question 26

position and description of TATA box

Answer 26

-25 | indicates transcription start site

Question 27

position and description of CAAT box

Answer 27

-50 | indicates "strong" promoter (makes a lot of mRNA)

Question 28

location and description of GC box

Answer 28

-80 | indicates "housekeeping" genes

Question 29

code for proteins needed all the time

Answer 29

housekeeping genes

Question 30

eukaryotic initiation involves

Answer 30

several transcription factors

Question 31

transcription factors sequentially bind to

Answer 31

TATA region and polymerase

Question 32

polymerase complex binds to

Answer 32

promoter

Question 33

activates polymerase via phosphorylation and transcription begins

Answer 33

TFIIH

Question 34

a short segment of DNA near eukaryotic promoters that bind transcription of certain genes

Answer 34

enhancers

Question 35

what allows for the interaction with RNA polymerase

Answer 35

formation of DNA loop

Question 36

do mRNA's require processing in prokaryotes

Answer 36

no

Question 37

three main types of mRNA processing in eukaryotes

Answer 37

5' capping 3' polyadenylation splicing

Question 38

addition of 7-methyl guanosine to the 5' end

Answer 38

5' capping

Question 39

the addition of 100-250 adenylate residues to the 3' end

Answer 39

3' polyadenylation

Question 40

the removal of introns and ligation of exons

Answer 40

splicing

Question 41

two characteristics of 5' cap

Answer 41

1. methylguanosine linked via 5' to 5' triphosphate | 2. 2' OH's of up to 3 neucleotides are methylated

Question 42

5' cap serves as a

Answer 42

recognition site for ribosome attachment and prevents transcript degradation by exonucleases

Question 43

what is the termination sequence of eukaryotic RNAs

Answer 43

AAUAAA

Question 44

two big functions of the poly A tail

Answer 44

help direct mRNA's out of the nucleus | protects 3' end from exonuclease degradation

Question 45

what does the length of the poly A tail say about the RNA

Answer 45

describes its longevity

Question 46

pre-mRNAs have short nucleotide sequences at the end of introns that serve as

Answer 46

splicing signals

Question 47

recognize consensus splice sites via RNA base pairing

Answer 47

snRNPs

Question 48

what makes a spliceosome

Answer 48

several snRNPs join together

Question 49

job of spliceosomes

Answer 49

cut out and attaches exon ends together

Question 50

where does RNA splicing occur

Answer 50

in in the nucleus

Question 51

introns may provide

Answer 51

cross over recombination sites

Question 52

facilitate recombination within proteins to allow novel protein function

Answer 52

exon shuffling