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Test your basic knowledge |
Molecular Biotechnology
Start Test
Study First
Subject
:
engineering
Instructions:
Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can
study here
.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.
This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. AARS charges the correct amino acid to tRNA in a two- step reaction.
araO2
Amino acyl- tRNA synthase
Initiation of Translation in Eukaryote
tRNA
2. 1. Synthesis of commercial products by recombinant organisms 2. Biopolymers 3. Bioremediation 4. Biomass utilization
DNA Replication
Impacts of Molecular Biotechnology
Housekeeping genes
Nonsense suppression
3. Operator site - araC binds to this site and represses its own transcription from the PC promoter. In the presence of arabinose - araC bound at this site helps to activate expression of Pbad promoter
Ribosomes
Pleiotropic
araO1
Polycistronic
4. A segment of DNA molecule contains the information required for synthesis of a functional biological product
Bacterial Transcription
Gene
Inducible expression
Operon
5. The repressor dimer (aporepressor) can't bind to the repressor. Transcription from the promoter is not stopped. When tryptophan is bound to the repressor dimer - the repressor changes configuration so that it can bind to the operator and transcriptio
Constitutive expression
TrpR Repression
Retrovirus
RNA
6. Inducer site; araC bound at this site can simultaneously bind to the araO2 site to repress transcription from the Pbad promoter. In the presence of arabinose - araC bound at this site helps to activate expression of Pbad promoter.
Negative regulation
Inducible expression
tRNA
araI
7. Codes for three enzymes needed to catalyze the metabolism of arabinose. The operon is regulated by araC gene product.
ara operon
Lac Operon
Components of Translation
Nonsense suppression
8. A cell that contains a nucleus and membrane bound organelles
Eukaryote
Retrovirus
Pleiotropic
Initiation
9. When arabinose is absent - there is no need to express the structural genes. AraC does this by binding simultaneously to araI and araO2 - making a looped DNA. This blocks access to Pbad promoter. AraC is an autoregulator of its own expression and the
Negative regulation
Repression
Open reading frame
RNA Primer
10. Release DNA - rewind DNA - release RNA; stop signals or rho mediated termination (hairpin is a palindromic GC- rich region followed by an AT- rich region; Rho is a termination factor that binds to nascent RNA) RNAP has sigma factor that recognizes pr
Termination:
Wobble
mRNA processing
RNA Primer
11. Eukaryotic. mRNA that codes for one protein
Merodiploid
3 Stages of DNA Replication
Monocistronic
Pleiotropic
12. Unvarying expression of gene
Ribosomes
Repression
Levels of Cells
Constitutive expression
13. Search for site to start transcription - unwind DNA; -35 region and pribnow region (-10 region).
RNA Primer
Initiation
Amino acyl- tRNA synthase
Induction
14. Replication > DNA > Transcription > RNA > Translation > Protein
Visualization of DNA
Levels of Cells
Central Dogma
tRNA
15. 1. LacI- makes an internal inducer -- NO. Found that lacI- doesn't dominate over lacI+ and is not always constitutive. 2. LacI- is a repressor protein -- YES. LacI+ dominates over lacI- because when both are together - lac operon is inducible. LacI m
Nonsense suppression
LacI Possibilities
Lac Operon
Ribosomes
16. Operons transcribed as single mRNA and mRNA codes for more than one protein.
Gene
Polycistronic
Regulated gene expression
Central Dogma
17. Gene products decrease in concentration under particular molecular circumstances
Merodiploid
Open reading frame
Bacterial Transcription
Repressible expression
18. 1. Initiation: unwind DNA at the origin of replication (ori) - bidirectional replications; regulated as required for cell division 2. Elongation: requires RNA primer to replicate 3. Termination: signaled by Ter sequence
RNA
DNA Replication
Ribosomes
3 Stages of DNA Replication
19. TrpE through trpA are five enzymes that catalyze the synthesis of the amino acid tryptophan from chorismic acid. If the cell has enough tryptophan - then it doesn't need to waste energy transcribing this mRNA. In the presence of tryptophan - the oper
Trp operon
Constitutive expression
What makes up a cell?
When tryptophan is high
20. The process of increasing the expression of inducible genes
Elongation (Protein)
Impacts of Molecular Biotechnology
Open reading frame
Induction
21. Start codon is usually ATG - first amino acid is n - formyl- methionine. It is assisted by initiation factors (IF) and requires ribosomal binding sites (RBS). It is a polycistronic protein translation (operon).
What makes up a cell?
Central Dogma
LacI Possibilities
Initiation of Translation in Bacteria
22. Select correct ribonucleotides; loss of sigma factor - transcription bubble - no need for primers
Elongation
Operon
Termination:
Pleiotropic
23. A unicellular organism that lacks a nucleus and membrane bound organelles
CAP
Prokaryote
Cells
Inducible expression
24. Attenuation
araI
Diauxie
TrpL
Cells
25. 1. Capping: 5' phosphate capped by 7- methyl guanosine and is a 5'-5' linkage instead of 5'-3' This makes RNA more stable 2. Intron removal 3. Export to cytoplasm 4. Polyadenylated mRNA precursor
mRNA processing
Initiation
Wobble
Negative regulation
26. 4. Cells + organelle 3. Supermolecular complexes 2. Macromolecules 1. Monomeric units
araI
Amino acyl- tRNA synthase
Levels of Cells
Elongation
27. Polymerase binds to lac promoter weakly by itself and results in low levels of transcription even in the absence of lacI. The activator recruits the polymerase to the promoter region and increases its affinity for the promoter
Monocistronic
Open reading frame
Wobble
Activation Lac Operon
28. 1. Nucleic acid hybridization: (a) bind single stranded DNA to a membrane support - (b) add single stranded labeled DNA (probe) under appropriate conditions - (c) wash the support to remove excess unbound labeled probe DNA - (d) detect the hybrid seq
Initiation
Repression
Bacterial Transcription
DNA diagnostic systems
29. Three sites recruit tRNA and forms peptidyl- tRNA bonds (E - exit; P - peptide; A - acceptor).
Termination:
Elongation (Protein)
What makes up a cell?
Central Dogma
30. Determines amino acid selection. A noncognate amino acid charge incorrectly to the tRNA will be inserted into the protein. Introduce new amino acid by using tRNA for UAG.
Gene
tRNA
Monocistronic
DNA diagnostic systems
31. Comprised of >50 proteins associated with rRNA units. Site of protein synthesis and binds mRNA and finds protein synthesis initiation sites. It also binds aa- tRNA and catalyzes peptide bond formation.
Ribosomes
Levels of Cells
Amino acyl- tRNA synthase
Regulated gene expression
32. Chromosome (contains host genetic information) - plasmids (prokaryotes; small - self- replicating DNA; supercoil) - free nucleotides
Types of DNA
DNA diagnostic systems
araI
Activation Lac Operon
33. A small catabolite molecule. Its level is determined by the level of glucose in the cell where glucose controls the rate of cAMP formation with ATP. When there is high glucose - there is low levels of cAMP. cAMP activator protein (CAP) has to bind cA
araI
Monocistronic
cAMP
Impacts of Molecular Biotechnology
34. The process in which an exact copy of the double strand DNA is made. It is a templated process and occurs from 5' to 3' end. DNAP - RNA primer; semiconservative (each strand is a template for the replication of the complementary strand)
Regulated gene expression
DNA Replication
When tryptophan is low
Central Dogma
35. Important to suppress mutations at 3rd position and you don't need to have a lot of stop codons; cells can be more flexible
Operon
Degeneracy
TrpR Repression
Merodiploid
36. When half DNA strand has been denatured. Determined by GC content (triple bond)
Elongation Factor Tu
Retrovirus
Negative regulation
Melting temperature (Tm)
37. When arabinose is present - it binds to araC and allosterically induces it to bind to araI instead araO2. If glucose is absent - then the presence of CAP bound to its site between araO1 and araI helps break the DNA loop and helps araC bind to araI
Induction
Nonsense suppression
Positive regulation
Elongation
38. Binds to CAP binding site. In conjunction with araC bound with arabinose - it assists RNAP in binding to the Pbad promoter
What makes up a cell?
CAP
Components of Translation
Termination:
39. Functions: enzymes - regulation - structural - cellular functions Polymers of amino acids and connected by peptide bonds. Can fold into complex structures.
Ribosomes
Molecular Biotechnology
Proteins
Constitutive expression
40. C - N - O - H make up 99% cell weight - 70% is water
DNA diagnostic systems
LacI Possibilities
cAMP
What makes up a cell?
41. In E. coli - DNAP III can unwind DNA (helicase) and replicate both strands of DNA. It also has proofreading activity and corrects mistakes 3' to 5' exonuclease
DNA Replication
Lac Operon
Initiation of Translation in Bacteria
DNAP
42. The process of decreasing the expression of inducible genes
When tryptophan is high
Repression
Merodiploid
Eukaryote
43. The small ribosomal subunit binds to 5'-G cap on processed mRNA (no RBS) - uses met instead of fmet for initiation; monocistronic translation
Elongation
Bacterial Transcription
Initiation of Translation in Eukaryote
Lac Operon
44. The ribosome translating the leader peptide arrives at the two tryptophan codons and has to wait for tryptophan. During this time - RNAP continues to transcribe. Stem loop between 2 and 3.
Central Dogma
CAP
Constitutive expression
When tryptophan is low
45. Operator site; araC bound at this site can simultaneously bind to the araI site to repress transcription from Pbad promoter
araO2
Prokaryote
mRNA processing
Positive regulation
46. EF-Tu GTP binds with an aminoacyl- tRNA and brings it to the ribosome. Once the correct aminoacyl- tRNA is positioned in the ribosome - GTP is hydrolyzed and EF-Tu* GDP dissociates away from the ribosome
Components of Translation
Retrovirus
Bacterial Transcription
Elongation Factor Tu
47. 1. mRNA: encodes genetic information 2. tRNA: transfer RNA - involved in protein synthesis (DNA to amino acids) 3. rRNA: ribosome RNA - involved in protein synthesis (polypeptide formation) 4. Ribozymes and RNAi - Can store genetic information and ca
DNA Replication
Types of DNA
Visualization of DNA
RNA
48. Production of commercial products generated by the metabolic actions of microorganisms.
Nonsense suppression
Polycistronic
Molecular Biotechnology
RNA Primer
49. In prokaryotes - related genes often arrayed in tandem. A unit of bacterial gene expression and regulation - recognized by a regulator gene product
mRNA processing
Operon
Wobble
TrpR Repression
50. Gene products increase in concentration under particular molecular circumstances
Eukaryotic Transcription
Inducible expression
Ribosomes
Diauxie