$1.$ A mutation is found in eIF$-2$ that impairs the initiation of translation. The mutation could

affect all but one of the following functions of eIF$-2.$ Which one would not be affected?

a$.$ The mutation prevents eIF$-2$ from binding to RNA.

b$.$ The mutation prevents eIF$-2$ from being phosphorylated.

c$.$ The mutation prevents eIF$-2$ from binding to GTP$.$

d$.$ The mutation prevents eIF$-2$ from binding to the $40$S ribosomal subunit.

$2.$ The addition of a ubiquitin group to a protein does what?

a$.$ increases the stability of the protein

b$.$ decreases translation of the protein

c$.$ increases translation of the protein

d$.$ marks the protein for degradation

$3.$ What part$($s$)$ of a gene produces a protein?

A$.$ Introns

B$.5\text{'}$ cap

C$.$ Exons

D poly $($A$)$ tail

E$.$ Stop Codon

$4.$ What requirement$($s$)$ are necessary to have an accurate translation?

a$.$ a correct match between tRNA and its amino acid

b$.$ a correct match between tRNA and anticodon

c$.$ aminoacyl$-$tRNA$-$synthetase enzyme activity

D$.$ A and B only

e$.$ all of the above

$5.$ The nascent polypeptide grows first on the carboxyl side and ends on the amino side.

a$.$ True

b$.$ False

$6.$ Which of the ribosome units is responsible for scanning the mRNA and sticking to the initiator

met$-$tRNA?

A$.$ Large ribosome subunit

B$.$ Small subunit of the ribosome

C$.$ Both subunits

D$.$ None, this step does not depend on the units of the ribosome

E$.$ None of the above

$7.$ What strategy could be used to determine if an mRNA was being actively translated?

a$.$ Sanger sequencing

b$.$ Western blot

C$.$ Differential centrifugation for mass separation

d$.$ Chip$-$seq

e$.$ all of the above

$8.$ Elongation factors facilitate one of the following processes

A$.$ Peptide bond formation

B$.$ Codon recognition

C$.$ Translocation of the nascent polypeptide

D$.$ A and B only

E$.$ all of the above

$9.$ What molecule provides the energy for the active process of translation $($elongation$)?$

A$.$ Transesterification

b$.$ NADH

c$.$ GTP

d$.$ ATP

E$.$ Pyrophosphate

$10.$ How do the synthetases select their tRNAs and amino acids?

A$.$ by charge, size, and hydrophobicity

B$.$ by size only

C$.$ by specific sequence and structural features found in the anticodon loop and acceptor stems

D$.$ A and C are correct

E$.$ B and C are correct

$11.$ Ribosomes are composed only of rRNA.

a$.$ True

b$.$ False

$12.$ EFtu, a GTPase, is a factor responsible for carrying aminoacyl$-$tRNA to the ribosome, what

would happen if a mutation prevents its ability to hydrolyze GTP$?$

a$.$ prevents amino acid$-$tRNA bonding

b$.$ aminoacyl$-$tRNA sticks to the E site and not to the A site

C$.$ prevents translocation of the nascent polypeptide.

d$.$ elongation inhibition by preventing tRNA acceptance at the ribosome site.

e$.$ Increases the speed of elongation

$13.$ Phosphorylation of $4$E$-$BPs is crucial for translation initiation. Why?

a$.$ this event triggers $4$E$-$BPs so that it can start translation

b$.$ this event causes $4$E$-$BPs to hijack the eIF$4$E factor

c$.$ this event will release the factor eIF$4$E so that it can start translation

d$.$ None of the above

$14.$ What would happen to the translation process if mTOR was constitutively active?

a$.$ increases protein synthesis

b$.$ constant phosphorylation of $4$E$-$BPs

c$.$ Reduced protein synthesis

d$.$ A and B are correct

e$.$ Only C is correct

$15.$ The translation initiation process begins with the recruitment of the initiator tRNA to the P

site of the $40$s subunit and then the binding of the mRNA to the tRNA$-40$ s complex, what has to

happen for the elongation process to begin?

a$.$ hydrolysis of GTP and the decommissioning of the initiation complex

b$.$ the $60$S subunit sticks to the $40$S subunit

c$.$ recruitment of the releasing factor on the A site

D$.$ A and B are correct

e$.$ they are all correct