Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
46 Cards in this Set
- Front
- Back
The Shine-Dalgarno sequence is a |
Prokaryotic mRNA sequence that binds 16S rRNA of the small ribosomal subunit |
|
The initiation phase of prokaryotic trasnaltion ends as the GTP molecule bound to ______ is hydrolysed to GDP and Pi |
IF-2 |
|
During the elongation phase of prokaryotic translation the aminoacyl-tRNA must first bind _____ before it can be positioned in the A site |
EF-Tu-GTP |
|
_____ is an enzymatic activity that hydrolyses the bond linking the completed polypeptide chain and the P sit tRNA |
Peptidyl transferase |
|
Prominent prokaryotic post-translational modifications include all of the following except A) GlycosylationB) MethylationC) Proteolytic processingD) PrenylationE) Phosphorylation |
Prenylation |
|
In prokaryotes most of the control of protein synthesis occurs at the level of ______.
A) TranslationB) TranscriptionC) ReplicationD) Reverse transcriptionE) Posttranslational modification |
Transcription |
|
The enzymatic activities coded by the lac operon include all of the following except:
A) Thiogalactoside transacylaseB) Lactose transferaseC) b-GalactosidaseD) Galactose permeaseE) None of the above are correct |
Lactose transferase |
|
Translocation in eukaryotes requires _____, which is a GTP binding protein.
A) eEF-1B) eEF-2C) eEF-3D) eEF-4E) None of the above are correct |
eEF-2 |
|
In eukaryotic translation the 40S complex binds the 60S subunit to form the _______initiation complex.A) 80SB) 88SC) 90SD) 100SE) 108S
|
80S |
|
________ provides the energy needed to move the ribosome along the mRNA.
A) ATPB) GTPC) UTPD) TTPE) All of the above are correct |
GTP |
|
Polypeptides containing signal peptides are called ________.
A) ZymogensB) PreproproteinsC) ProproteinsD) All of the above are correctE) None of the above are correct |
Preproproteins |
|
Phosphorylated dolichol, a polyisoprenoid found in ER membrane, is involved in
A) Polypeptide synthesisB) Proteolytic cleavage reactionsC) Lipophillic modification reactionsD) Hydroxylation reactionsE) Glycosylation reactions |
Glycosylation Reactions |
|
All of the following are involved in signal peptide processing except
A) Ribosomal polypeptide translocation factorB) SRP receptor proteinC) Docking proteinD) TransloconE) Stop transfer signal |
Ribosomal polypeptide translocation factor |
|
The phrase “global control” refers to
A) Large alterations in mRNA translation patternsB) Large alterations in mRNA synthesis patternsC) Specific changes in rRNA synthesisD) Specific changes in mRNA synthesisE) Changes in transcript localization patterns |
Large alterations in mRNA translation patterns |
|
Translational frameshifting
A) Results in the synthesis of more than one polypeptide from a single mRNAB) Has been observed in cells infected by retrovirusesC) Is the result of a +1 or –1 change in the reading frame of an mRNAD) Both A and C are correctE) All of the above are correct |
All of the above are correct
|
|
All of the following statements concerning eukaryotic mRNA are true except
A) Only a small portion of mRNA enters the cytoplasmB) Most hnRNA is processed into mRNAC) Export of mRNA through muclear pores is carefully controlledD) mRNA export usually requires a 5’-cap and a 3’-poly A tailE) None of the above are correct |
Most hnRNA is processed into mRNA |
|
Eukaryotic mRNA stability involves
A) Reversible adenylationB) The length of poly (A) tailsC) The binding of specific proteins to certain mRNA sequencesD) The action of various nucleasesE) All of the above are correct |
All of the above are correct |
|
_______ are a group of molecules that mediate protein folding.
A) Hsp 70sB) ChaparoninsC) Docking proteinD) Both A and B are correctE) All of the above are correct |
Both A and B are correct |
|
The mRNA that codes for ________ possesses an iron response element.
A) CollagenB) ElastinC) GlobinD) FerritinE) Thiogalactoside transacetylase |
Ferritin |
|
Chloramphenicol is an antibiotic that
A) Inhibits prokaryotic peptidyl transferaseB) Causes mRNA misreading via binding to the 30S subunitC) Interferes with aminoacyl-tRNA binding via binding to 30S subunitD) Inhibits eukaryotic peptidyl transferaseE) Inhibits prokaryotic peptide chain elongation |
Inhibits prokaryotic peptidyl transferase |
|
Cycloheximide is an antibiotic that
A) Inhibits prokaryotic peptidyl transferaseB) Causes mRNA misreading via binding to 30s subunitC) Interferes with aminoacyl-tRNA binding via binding to the 30S subunitD) Inhibits eukaryotic peptidyl transferaseE) Inhibits prokaryotic peptide chain elongation |
Inhibits eukaryotic peptidyl transferase |
|
Tetracycline is an antibiotic that
A) Inhibits prokaryotic peptidyl transferaseB) Causes mRNA misreading via binding to 30S subunitC) Interferes with aminoacyl-tRNA binding to the 30S subunitD) Inhibits eukaryotic peptidyl transferaseE) Inhibits prokaryotic peptide chain elongation |
Interferes with aminoacyl-tRNA binding to the 30S subunit
|
|
Erythromycin is an antibiotic that A) Inhibits prokaryotic peptidyl transferaseB) Causes mRNA misreading via binding to 30S subunitC) Interferes with aminoacyl-tRNA binding via binding to the 30S subunitD) Inhibits eukaryotic peptidyl transferaseE) Inhibits prokaryotic peptide chain elongation |
Inhibits prokaryotic peptide chain elongation |
|
Which of the following antibiotics would be most toxic for humans
A) TetracyclineB) ChloramphenicolC) StreptomcyinD) CycloheximideE) Erythromycin |
Cycloheximide |
|
Ribonucleoprotein particles
A) Contain an mRNAB) Contain several types of proteinC) Are found only in prokaryotesD) Both A and B are correctE) All of the above are correct |
Both A and B are correct |
|
_________ is a translation factor that possesses a unique histidine residue that can bemodified to form dipthamide
A) IF-2B) EF-TuC) EF-TsD) eEF-1E) eEF-2 |
eEF-2 |
|
Hydroxylation is a posttranslational modification that
A) Requires ascorbic acidB) Is catalyzed by several mixed function oxidasesC) Is required for the structural integrity of globinD) Both A and B are correctE) All of the above are correct |
Both A and B are correct |
|
In prokaryotes posttranslational methylation reactions are associated with
A) Signal transductionB) ChemotaxisC) S-AdenosylmethionineD) All of the above are correctE) None of the above are correct |
All of the above are correct |
|
The half-lives of prokaryotic mRNA usually varies between
A) 1 and 3 secondsB) 1 and 3 minutesC) 1 and 3 hoursD) 3 and 10 hoursE) None of the above are correct |
1 and 3 minutes |
|
Peptidyl transferase is an enzymatic activity that
A) Catalyzes the release of polypeptides from the ribosomesB) Is found in an rRNA component of ribosomesC) Catalyzes the nucleophilic attack of the A site a-amino group on the carbonyl carbonof the P side amino acidD) Catalyses peptide bond formationE) All of the above are correct |
All of the above are correct |
|
Energy for ribosome function is provided by
A) ATPB) GTPC) PhosphoenolpyruvateD) Hydrolysis of pyrophosphateE) Both A and B are correct |
GTP |
|
Unlike the protein synthesis mechanism in the cytoplasm of eukaryotic cells,mitochondria have _______ stop codes.
A) 1B) 2C) 3D) 4E) 5 |
4 |
|
An analysis of the wobble hypothesis suggests that a minimum of _______ RNA’sare required to translate all 61 codons plus one for a start codon.
A) 22B) 32C) 16D) 62E) 30 |
32 |
|
Translation begins with
A) ElongationB) InitiationC) TerminationD) TargetingE) tRNA synthesis |
Initiation |
|
Which of the following is a type of posttranslational modification?
A) Removal of signal peptidesB) CarboxylationC) MethylationD) PhosphorylationE) All of the above |
All of the above |
|
Protein synthesis requires _____ high energy phosphate bonds per peptide bond.
A) 1B) 2C) 3D) 4E) 5 |
4 |
|
An amino acid coded for by a stop signal is
A) PyrrolysineB) LysineC) CysteineD) SelenocysteineE) Both A and D are correct |
Both A and D are correct |
|
In eukaryotes which of the following amino acids is often hydroxylated after proteinsynthesis?
A) ProlineB) TyrosoneC) ArginineD) MethionineE) All of the above |
Proline |
|
Which of the following amino acids is sometimes carboxylated after protein synthesisin eukaryotes
A) GlutamateB) AspartateC) PhenylalanineD) LysineE) Arginine |
Glutamate |
|
Prokaryotes exclusively use which of the following translational controlmechanisms?
A) Negative translational control of ribosomal proteinsB) Global controlsC) RNA specific controlsD) Allosteric modifications of ribosomesE) Energy depletion |
Negative translational control of ribosomal proteins |
|
Which of the following is a synonymous codon with UCU?
A) AAUB) UCAC) GAUD) AAAE) CUG |
UCA |
|
Protein synthesis in bacteria involves six functional centers. Which of the followingis not one of those centers?
A) Decoding centerB) Aminase transfer centerC) Pepidyl transfer centerD) GTPase associated regionE) A site |
Aminase transfer center |
|
The peptide emerging from the exit tunnel first encounters a molecular factor called
A) Trigger factorB) Signal factorC) Linkage chaperoneD) P-siteE) Translation factor |
Trigger factor |
|
Eukaryotic initiation begins with the assembly of ________________.
A) Preinitiation complexB) Cap-binding complexC) Poly-binding complexD) 48S Initiation complexE) Translational initiation complex |
Preinitiation complex |
|
Which of the following compounds is referred to as the twenty first amino acid
A) SelenocysteineB) GlucolysineC) CysteineD) DehydroxyalinineE) D-Lysine |
Selenocysteine |
|
During synthesis of secreted proteins; binding of the ribosome to the ER membraneis mediated by
A) The transloconB) SRP and SRP receptor proteinC) Signal peptidaseD) Cotranslational transferE) Posttranslational translocation |
SRP and SRP receptor protein |