Transcription Translation

Question 1

Polycistronic

Answer 1

One promotor region transcribes multiple genes at one time.

MRNA is considered to be Polycistronic

-prokaryotic version of transcription

Question 2

Monocistronic

Answer 2

One promoter region transcribes 1 gene

• mRNA is said to be monocistronic
• eukaryotic version of transcription

Question 3

HnRNA

Answer 3

Version of mRNA where introns are not spliced out yet.

• once spliced, is officially mRNA

Question 4

3 steps of transcription that are common in prokaryotic/eukaryotic cells

Answer 4

Initiation: binding of RNA polymerase to promotor

Elongation: transcription of HnRNA

Termination: stop codon reached and RNA Polymerase leaves

Question 5

TATA box

Answer 5

In both prokaryotes and eukaryotes helps RNA polymerase determines where promotor is.

Directly upstream of promotor.

Question 6

Alpha factor

Answer 6

Prokaryotic factor that binds to RNA polymerase until promotor is found.

RNA polymerase is inactive while bound to alpha factor

Question 7

RNA polymerase holoenzyme

Answer 7

Prokaryotic subunit that transcribes RNA

Question 8

RNA is transcribed in what direction

Answer 8

5’ - 3’

Question 9

RNA polymerase 1

Answer 9

Eukaryotic polymerase that produces rRNA

Question 10

RNA polymerase 2

Answer 10

Eukaroytic polymerase that produces mRNA & MiRNA

Question 11

RNA polymerase 3

Answer 11

Eukaryotic polymerase that produces tRNA and siRNA

Question 12

Rho independent termination

Answer 12

Found in prokaryotes

• forms a hairpin strucutre that base pairs with itself and stops elongation

Question 13

Rho dependent transcription

Answer 13

Prokaryotic termination requiring Rho protien

Question 14

Poly(A) sequence

Answer 14

Initiates termination of transcription in eukaryotes via CPSF & CstF

Question 15

Actinomycin D

Answer 15

Inhibits elongation/initation in prokaryotes and eukaryotes

Question 16

Rifampin

Answer 16

Prevents RNA polymerase from elongating past 3 nucleotides in Prokaryotic and transcription

Question 17

(A)-amanitin

Answer 17

Inhibits Eukaroytic Polymerases 2

• cant produce mRNA

Question 18

Capping mRNA

Answer 18

Attaches methylguanosine to 5’ end of mRNA molecule via triphosphate linkage.

• MG allows for binding of ribosome to mRNA
• triphosphate linkage prevents degradation from cytosolic nuclease

Question 19

3’ poly-A-tail

Answer 19

Attaches 40-200 adenosine bases
(Polyadenylation signal)

• prevents degradation by nuclease

Question 20

Splicing of introns

Answer 20

SnRNAs “snurps” splice out introns based on splice sites

Question 21

Designations of snRNAs

Answer 21

U1, U2, U4, U5 & U6

Question 22

Characteristics of genetic code

Answer 22

Specific

Universal

Degenerative

Continuous

Non-overlapping

Question 23

Specific

Answer 23

Each 3 nucleotides form 1 codon

Question 24

Degenerative

Answer 24

Multiple different codons can create the same amino acid

“Wobble”

Question 25

Non-overlapping

Answer 25

Each codon is read in 3 nucleotide window

Question 26

T-RNA

Answer 26

Binds AA’s to 3’ end covalently and brings them to the mRNA

Question 27

R-RNAs

Answer 27

Make up 80% of all RNAs Form small and large ribosomal subunits w/ help from ribosomal proteins to conduct protein synthesis

Question 28

Two size of eukaryotic ribosomal subunits

Answer 28

60S & 40S

Question 29

Two size in prokaryotic ribosomal subunit

Answer 29

50S & 30S

Question 30

Streptomycin

Answer 30

Binds to 30S subunit in prokaryotes and prevents translation

Question 31

Initiation of translation in prokaryotes

Answer 31

Interaction of shine-delgarno sequence with 16S ribosomal RNA Causes formation of 30S subunit

Question 32

Tetracyclines

Answer 32

Interact with 30S subunit in prokaryotes and blocks tRNA to the A site

Question 33

Puromycin

Answer 33

acts as tRNA and accepts peptides from P site haunting elongation and premature termination in both prokaryotes and eukaryotes

Question 34

Chloramphenicol

Answer 34

Inhibits prokaryotic peptidyltrasnferases preventing peptide bond formation between amino acids

Question 35

Erythromycin

Answer 35

Inhibits translocation in prokaryotes by irreversibly binding to 50S subunit of ribosome. - prevents peptide form leaving ribosome

Question 36

Polysomes

Answer 36

Multiple ribosomes in eukaryotes can come together and create polypeptides faster.

Question 37

Chaperone proteins and heat shock protiens

Answer 37

Help in proteins folding correctly - requires ATP

Question 38

Ubiquitin

Answer 38

Targets proteins for degradation by a proteasomes - proteasomes require ATP

Question 39

Amyloid fibrils

Answer 39

Insoluble aggregations of misfolded proteins - found in alzheimers, Parkinson’s, Huntington’s and mad cow disease

Question 40

I-cell disease

Answer 40

Defective glycosylation post-translation modification causes mannose sugar to not be attached to lysosomal enzymes. - toxic enzymes are floating around in cells causing death .

Question 41

Methylation of peptides

Answer 41

Post translational modification. - adds methyl groups to lysine residues and reduce charge on the protein.

Question 42

Hydroxylation

Answer 42

Post translational modification. - adds hydroxyl groups to proline and lysine residues making the protein more stable

Question 43

Phosphorylation

Answer 43

Post-translational modifications Adds or removes phosphate groups to energize or de energize proteins

Question 44

Glycosylation

Answer 44

Post-translational modification Adds carbohydrate groups to allow proteins to cross lipid membranes (specifically into lysosomes and other cellular membrane organelles)