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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. 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).
Wobble
Open reading frame
Initiation of Translation in Bacteria
Elongation Factor Tu
2. Attenuation
Gene
araO1
Degeneracy
TrpL
3. Operator site; araC bound at this site can simultaneously bind to the araI site to repress transcription from Pbad promoter
Central Dogma
Housekeeping genes
Induction
araO2
4. Gene products increase in concentration under particular molecular circumstances
RNA Primer
Inducible expression
When tryptophan is high
What makes up a cell?
5. 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
Termination:
Elongation
Repression
Negative regulation
6. The process of increasing the expression of inducible genes
Gene
Elongation
When tryptophan is low
Induction
7. Genes for products that are required at all times.
Housekeeping genes
Prokaryote
Wobble
Melting temperature (Tm)
8. Eukaryotic. mRNA that codes for one protein
CAP
Monocistronic
Melting temperature (Tm)
ara operon
9. Need to remove introns before changing into mRNA - then take mRNA out of the nucleus. Has 3 RNAP (RNAP I synthesizes rRNA - II synthesizes mRNA - III synthesizes tRNA and small rRNA). Transcription factors are similar to sigma factors.
Proteins
Positive regulation
Bacterial Transcription
Eukaryotic Transcription
10. A strand segment complementary to the template with a free 3'OH group
Cells
Wobble
RNA Primer
LacI Possibilities
11. Multiple effects from a single gene
Elongation
Pleiotropic
DNAP
Melting temperature (Tm)
12. 1. mRNA - template for protein synthesis 2. tRNA - carrier of amino acid (the adaptor)3. aminoacyl- tRNA synthetase - pairs tRNA with the cognate amino acid - needs ATP 4. ribosome - site of protein synthesis - read in three frames - start codon is A
Pleiotropic
Repressible expression
Initiation of Translation in Eukaryote
Components of Translation
13. Chromosome (contains host genetic information) - plasmids (prokaryotes; small - self- replicating DNA; supercoil) - free nucleotides
Amino acyl- tRNA synthase
araO1
Types of DNA
RNA Primer
14. A cell that contains a nucleus and membrane bound organelles
Inducible expression
Elongation Factor Tu
Eukaryote
3 Stages of DNA Replication
15. Unvarying expression of gene
Constitutive expression
Amino acyl- tRNA synthase
Eukaryote
When tryptophan is low
16. Gene products decrease in concentration under particular molecular circumstances
Repressible expression
Initiation
Wobble
Elongation Factor Tu
17. 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
araO1
mRNA processing
Central Dogma
Negative regulation
18. 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
araO2
Eukaryotic Transcription
Termination:
Activation Lac Operon
19. The first two bases of the codon always form strong Watson -Crick base- pairing. The first base in the anticodon determines the number of codons a tRNA can recognize. The first position in anticodon is often modified to inosine to facilitate wobble b
Impacts of Molecular Biotechnology
Repression
Wobble
Bacterial Transcription
20. Reverse Transcriptase
Housekeeping genes
Retrovirus
DNA diagnostic systems
Degeneracy
21. Nonsense mutation in gene that results in truncated protein can be lethal. Sometimes a second mutation arises that counteracts the effects of the mutation. Amber stop codon (UAG/TAG/etc) and amber suppressor tRNA (CUA/etc) can restore protein size an
TrpL
ara operon
Constitutive expression
Nonsense suppression
22. A segment of DNA molecule contains the information required for synthesis of a functional biological product
Repression
Nonsense suppression
Positive regulation
Gene
23. 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
Open reading frame
TrpL
mRNA processing
RNA
24. Ribosome doesn't stop at trp codons and stem loop forms between 3 and 4. RNAP stops prematurely (attenuated)
When tryptophan is low
When tryptophan is high
mRNA processing
Impacts of Molecular Biotechnology
25. 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
Lac Operon
DNA diagnostic systems
Ribosomes
cAMP
26. 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)
DNA Replication
Gene
Activation Lac Operon
Housekeeping genes
27. 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
LacI Possibilities
Amino acyl- tRNA synthase
TrpR Repression
Melting temperature (Tm)
28. Functions: enzymes - regulation - structural - cellular functions Polymers of amino acids and connected by peptide bonds. Can fold into complex structures.
araI
Inducible expression
Amino acyl- tRNA synthase
Proteins
29. A unicellular organism that lacks a nucleus and membrane bound organelles
DNA diagnostic systems
Eukaryote
Prokaryote
Regulated gene expression
30. 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
Impacts of Molecular Biotechnology
mRNA processing
RNA
Monocistronic
31. The small ribosomal subunit binds to 5'-G cap on processed mRNA (no RBS) - uses met instead of fmet for initiation; monocistronic translation
Initiation of Translation in Eukaryote
tRNA
Repression
Proteins
32. In the presence of glucose and lactose - bacteria grows first on glucose - then growth levels off - and starts growing on lactose. You have diauxie growth because (1) CAP helps recruit RNAP. in the presence of glucose - CAMP is low so it can't bind t
DNAP
Initiation of Translation in Bacteria
Diauxie
Wobble
33. In prokaryotes - related genes often arrayed in tandem. A unit of bacterial gene expression and regulation - recognized by a regulator gene product
Pleiotropic
Positive regulation
Operon
Merodiploid
34. 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.
tRNA
Induction
araO2
Proteins
35. Operons transcribed as single mRNA and mRNA codes for more than one protein.
Elongation
Central Dogma
cAMP
Polycistronic
36. Binds to CAP binding site. In conjunction with araC bound with arabinose - it assists RNAP in binding to the Pbad promoter
Eukaryote
Trp operon
Retrovirus
CAP
37. 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
LacI Possibilities
Regulated gene expression
Diauxie
Wobble
38. 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.
araI
TrpR Repression
Housekeeping genes
Polycistronic
39. Codes for three enzymes needed to catalyze the metabolism of arabinose. The operon is regulated by araC gene product.
Nonsense suppression
ara operon
Levels of Cells
Central Dogma
40. 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
Initiation
Elongation Factor Tu
Visualization of DNA
araO2
41. AARS charges the correct amino acid to tRNA in a two- step reaction.
When tryptophan is high
DNAP
TrpR Repression
Amino acyl- tRNA synthase
42. 1. Synthesis of commercial products by recombinant organisms 2. Biopolymers 3. Bioremediation 4. Biomass utilization
Negative regulation
araI
Initiation of Translation in Bacteria
Impacts of Molecular Biotechnology
43. 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
Degeneracy
Trp operon
Components of Translation
DNAP
44. A reading frame without termination codon among 50 or more codons. Usually correspond to genes that encode proteins
Repressible expression
Open reading frame
Trp operon
Diauxie
45. Structural and functional units of life. All organisms are made of cells - all cells are derived from preexisting cells - the purpose of a microorganism is to make another microorganisms as quickly as possible; alter metabolism of microorganism to ma
Components of Translation
Levels of Cells
RNA
Cells
46. Important to suppress mutations at 3rd position and you don't need to have a lot of stop codons; cells can be more flexible
Gene
Degeneracy
Operon
Eukaryote
47. A templated process just like in DNA replication and there is no processing steps.
Trp operon
Bacterial Transcription
DNA diagnostic systems
Eukaryotic Transcription
48. C - N - O - H make up 99% cell weight - 70% is water
Initiation
Merodiploid
DNA diagnostic systems
What makes up a cell?
49. 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
Elongation Factor Tu
DNA Replication
Activation Lac Operon
Positive regulation
50. Expression levels rise and fall in response to molecular signals
Amino acyl- tRNA synthase
ara operon
Monocistronic
Regulated gene expression