CH 7 quiz 3

Question 1

Central Dogma

Answer 1

DNA —-> transcription to RNA
RNA —-> Translation to Protein
Protein

Question 2

Uracil vs Thymine

Answer 2

Uracil - RNA
Thymine - DNA

Question 3

OH group on Ribose

Answer 3

changes interactions and causes the shape difference

Question 4

Shape of DNA and RNA

Answer 4

double helixes

Question 5

Transcription produces…

Answer 5

RNA that is complimentary to one strand of DNA

Question 6

RNA polymerase

Answer 6

temporarily unwinds DNA to synthesize RNA with energy from ribonucleoside triphosphate from 5’ end

Question 7

mRNAS

Answer 7

messenger RNA - Code for Proteins

Question 8

rRNAs

Answer 8

Ribosomal RNAs - form core of ribosomes structure and catalyze protein synthesis

Question 9

tRNAs

Answer 9

Transfer RNAs - serve as adaptors between mRNA and amino acids during protein synthesis

Question 10

lncRNAs

Answer 10

long noncoding RNAs - act as scaffolds and serve other diverse functions

Question 11

Promoter

Answer 11

specific sequence of DNA that RNA poly recognizes to begin transcription

Question 12

Terminator

Answer 12

specific sequence of DNA that signals RNA poly to stop transcription

Question 13

Promoter vs terminator in transcription

Answer 13

Promoter not transcribed
Terminator is transcribed

Question 14

Sigma Factor

Answer 14

binds to promoter region with RNA polymerase. is released once RNA synthesis starts

can rebond to RNA poly when after transcription

*only bacterial transcription

Question 15

Eurkaryotes vs Bacterial RNA polymerases

Answer 15

Eukaryotes - have 3 with many regulatory proteins or ( accessory proteins )

Bacteria - have only 1 with one regulatory protein as well - sigma factor

Question 16

RNA poly I
RNA poly II
RNA poly III

Answer 16

I - transcribes most rRNA (translation)
II - Transcribes all protein-coding genes
III - Transcribes tRNA genes, and many others

Question 17

TATA Box

Answer 17

recognized by subunit of general transcription factor called TFIID, called TATA-binding protein (TBP)

Question 18

TFIID

Answer 18

distorts DNA and enables binding of TFIIB

Question 19

after TFIID…

Answer 19

allows rest of general transcription factors and RNA poly to assemble at promoter

Question 20

TFIIH

Answer 20

Opens double helix and phosphorylates RNA poly II allowing transcription to begin

Question 21

RNA vs DNA structure

Answer 21

single stranded RNA folds up

Question 22

elongation factors

Answer 22

3 Elongation facotrs allow RNA poly to transcribe through proteins that wrap up DNA

Function by forming a wedge that pries the DNA off the histone

Question 23

Eukaryotic mRNAs processing

Answer 23

exported and translated by ribosomes in cytosol

Capping, Splicing, and polyadenylation

Question 24

Phosphorylation of the tail of RNA II allows

Answer 24

RNA processing proteins to assemble there

Question 25

5' cap 3' cap

Answer 25

5' - Triphosphate w modified Guanine 3' - Poly A tail

Question 26

Polyadenylation

Answer 26

addition of a few hundred A nucleotides to 3' end of RNA molecule

Question 27

Benefits of polyadenylation and capping

Answer 27

-increase stability of eukaryotic mRNA -facilitate export to cytosol -mark the molecule as an mRNA molecule

Question 28

Protein coding genes are interrupted by...

Answer 28

Introns, into trash Exons, Expressed

Question 29

Introns removed by

Answer 29

RNA splicing from Pre-mRNAs

Question 30

Bacteria coding

Answer 30

have no introns / exons

Question 31

snRNP

Answer 31

Small nuclear riboproteins, contain snRNA that recognize splice-site sequences

Question 32

U1

Answer 32

recognizes the 5' splice site

Question 33

U2

Answer 33

recognizes the lariat branch point site through complimentary base pairing

Question 34

U6

Answer 34

double checks the 5' splice site by displacing U1 and base pairing with intron sequence itself

Question 35

Alternative splicing

Answer 35

cell can decide what exons to include for a variety of functions from the same amount of exons

Question 36

RNA synthesis takes place in

Answer 36

membraneless compartments within nucleus

Question 37

Mature mRNAs are exported...

Answer 37

nuclear transport receptor associates with the mRNA and guides it through a nuclear pore. In cytosol the mRNA can shed these proteins and bind new ones to initiate protein synthesis.