Multiple choice question for engineering
1. Promoter-probe vectors are used often. Choose the correct statement for these vectors.
a) They are used for identifying sequences that can function as promoter in vivo
b) It contains a reporter gene which contains its promoter along
c) The reporter gene is having a cloning site
d) After insertion of DNA into the cloning site, selection of plasmids is carried out by blue white screening
2. GFP is one of a marker which is used for screening libraries in hosts other than E. coli. Choose the incorrect statement for GFP.
a) It stands for Green Fluorescent Protein
b) It is obtained from a bio-luminescent jellyfish and produces a protein aequorin which emits blue light
c) The blue light is produced because of binding of sodium ions
d) The absorbed blue light produces green light which can be detected further
3. Luciferase genes are also used at times for detection. Choose the correct statement for them.
a) They are obtained from fire flies only
b) The detection requires provision of substrate which produces light
c) Enzymes such as beta-galactosidase requires substrate X-gluc to produce light
d) Lucifearse genes are preferred over fluorescent proteins
4. In case of promoter-probe vectors, the same or related species should be as a vector whose DNA is to be screened. Is the given statement true or false?
5. Sequences that can function as origins of replication are called as:
a) partial replicating sequences
b) self replicating sequences
c) autonomously replicating sequences
d) modified replicating sequences
6. Screening is often carried out for a sequence that interacts with a protein for which already a clone is present. It is carried out in which host?
a) Bacterial host
b) Fungal host
c) Parasitic host
d) Yeast host
7. In two hybrid screening system, the activator binds through _______ domain to a sequence upstream of the gene under its control, and ________ domain stimulates transcription.
a) DNA binding, activation
b) Activation, DNA binding
c) Activation, transcription
d) DNA binding, transcription
8. For two hybrid systems, activation domains can be present in different proteins also rather than being on a single protein. A sequence encodes _______ protein for which we want to find an interacting protein.
9. The transcription domain is ________ if some of the bait and prey proteins are non-specific in nature?
d) may be activated or not
10. _____ should enter the cell in the case of activation of reporter gene for two hybrid system.
a) Bait protein
b) Prey protein
c) Both bait and prey protein
d) Either one of them
11. Protein-protein interactions such as in electron transport lead to activation of reporter gene. Is the given statement true or false?
1. The term ‘endonuclease’ refers to cutting the DNA sequence from:
a) only within the polynucleotide chain, not at the ends
b) the ends of the chain
c) anywhere in the chain
d) exactly in the middle of the chain
2. The restriction endonuclease is having a defence mechanism in bacterial system against foreign DNA such as viruses. But how it is able to protect its own DNA?
a) By methylation of bacterial DNA by restriction enzyme
b) By methylation of foreign DNA by restriction enzyme
c) By phosphorylation of bacterial DNA by restriction enzyme
d) By phosphorylation of foreign DNA by restriction enzyme
3. Even after replication, how the modified DNA remains protected?
a) It remains protected because of conservative mode of replication
b) It remains protected because of semi-conservative mode of replication
c) The mode of replication has no role to play in protection
d) It is again modified after replication
4. How many classes of restriction enzymes are there?
5. Type II cuts the sequence in the following way:
a) Within the recognition sequence
b) At 100-1000 nucleotides away from the recognition sequence
c) At 27-30 nucleotides away from the recognition sequence
d) It cuts randomly
6. After cleaving the sequence, the nature of the ends created by the type II endonuclease is:
a) The ends created are always single stranded
b) The ends created are always double stranded
c) Either the ends are single stranded or they are double stranded
d) One end is single stranded and one end is double stranded
7. A sequence is having two ends, 5’ and 3’. Which of the following statements is correct regarding the nature of the ends?
a) The 5’ end is having hydroxyl group
b) The 5’ end is having phosphate group
c) The 3’ end is having phosphate group
d) Any group can be present at any end
8. Blunt ends created by the restriction endonuclease can be joined. True or false?
9. The recognition sequence for BamHI is 5’ G|GATCC 3’. The ‘|’ represents the cutting site. What can be inferred about the ends from it?
a) The ends created are double stranded
b) The single stranded end is 5’ in nature
c) The single stranded end is 3’ in nature
d) To decide about the nature of the ends more information is needed
10. The recognition sequence of Sau3A is 5’ |GATC 3’ and that for DpnI is 5’ GA|TC 3’. Which of the statements is true?
a) The ends created by both the enzymes are compatible
b) The ends created by both the enzymes are not-compatible
c) The ends created by DpnI are single stranded
d) The ends created by Sau3A are single stranded
11. The recognition sequence is at times palindromic in nature. Which of the following statements is correct in respect to it?
a) The molecules which are cut by the same enzyme, anneal only if the sequence is palindromic in nature
b) When the molecules are cleaved by the same enzyme and the recognition sequence is palindromic in nature, there is no effect on annealing
c) There are increased chances of annealing if the recognition sequence is palindromic in nature
d) The term ‘palindromic’ can be used whether the sequence is read from 5’ to 3’ or 3’ to 5’
12. If all the nucleotides are present with equal frequencies and at random, what are the chances of having a particular four nucleotide long motif?
1. At times screening is done for the protein product of DNA of interest rather than the sequence itself. How many methods are there to carry out this?
2. Choose the correct statement if the screening is carried out by screening by expression in vivo.
a) The proportion of recombinants carrying gene of interest is small
b) The recombinants carrying gene of interest don’t complement the host mutation
c) Mutation should be affecting many genes
d) Most of the products selected would be result of complementation
3. Choose the incorrect statement in respect to host used.
a) The host must carry mutation for the gene of interest
b) The host should not contain restriction enzymes
c) The host if having restriction enzymes, then the incoming DNA should not be methylated
d) The host should be deficient in recombination
4. If the gene to be screened belongs to prokaryotic species then there are chances that it is not expressed. Is the given statement true or false?
5. If the library to be screened and the host belong to different species, then it is called as:
a) homologous selection
b) heterologous selection
c) intraspecies selection
d) mixed selection
6. The direct selection allows _______ number of recombinants to be screened and _______
a) less, slowly
b) less, quickly
c) more, quickly
d) more, slowly
7. Xenopus oocyte cells are also used at time to carry out screening. Choose the incorrect statement for this procedure.
a) DNA from collections is transcribed within in vitro and the transcription products are microinjected into oocytes
b) The RNA is translated within oocytes
c) Screening is carried out on the basis of DNA
d) The screening is helpful for the proteins whose function can be easily screened such as transport of ions
8. In the case of ligand binding by the expressed protein, the library can be screened by:
a) immunochemically, by the use of antibodies
b) ligands if the sequence we are looking for encodes a protein specific to a ligand
c) using a specific DNA sequence which can bind to the protein encoded by the sequence of interest
d) using all the above methods given above
9. In the case of immunochemical screening, the position of ________ antibody is detected by________ antibody.
a) secondary, primary
b) primary, secondary
c) primary, tertiary
d) secondary, tertiary
10. The ligand should bind to a single protein only for the screening process. Is the given statement true or false?
11. Choose the incorrect statement for panning.
a) It is a variant of ligand binding approach.
b) The ligand is immobilized on the solid support and the cells are passed over it
c) If the ligand-binding domain is exposed on surface of the any recombinant molecules then they will bind to ligand
d) They are not useful for scanning libraries in cultured mammalian cells
12. If screening is carried out by using a combination of nascent peptide and mRNA, then it is called as:
a) nascent peptide display
b) mRNA display
c) ribosome display
d) ribozyme display
1. A megaprimer method is a ____ stage approach and uses _____ oligonucleotide primers.
a) two, two
b) two, three
c) one, two
d) one, three
2. Choose the correct statement.
a) There are two flanking primers and they are having mutations
b) There is one primer which anneals the target sequence and is having mutation
c) Either of the flanking primers or the primer is annealing to the target sequence is having mutation
d) One of the flanking primer and the primer annealing to the target sequence is having mutation
3. PCR using the mutagenic primer and one of the flanking primers is used to carry out amplification and generates a product corresponding to the part of the gene. It is called as megaprimer. Is the given statement true or false?
4. Sometimes mutagenesis is carried out with the help of primers. Choose the correct statement with respect to it.
a) Double stranded circular molecule is used as a template
b) Mutation is introduced into one of flanking primers
c) Single stranded circular molecule is used as a template
d) After amplification, mutation is introduced into one strand
5. If PCR is used to introduce random mutations rather than specific mutations, it is called as:
a) mutagenic PCR
b) error-prone PCR
c) random PCR
d) general PCR
6. For the selection of the molecules having mutated sequence, which of the statement is true?
a) It is suitable for methods which are PCR based
b) It is suitable for methods which are not PCR based
c) It is suitable for both PCR and not PCR based
d) Selection of molecules with mutant sequence is not possible
7. Choose the incorrect statement for the methodology of selection of molecules with mutant sequences.
a) A vector is used which is having antibiotic resistance gene
b) Apart from antibiotic resistance gene, a second antibiotic resistance gene is also present
c) There are two mutagenic primers which are used
d) The second strand synthesis is carried out by only one primer
8. Once second strand synthesis is carried out, it is introduced into host. Host is having which mutation?
a) mutS mutation
b) mutD mutation
c) mutE mutation
d) mutG mutation
9. Replication by first strand leads to the formation of mutated molecules and functional antibiotic resistant gene. Is the given statement true or false?
10. In a phosphothiorate nucleotide, oxygen atom is replaced by with atom?
11. What is the function of ung gene?
a) It is responsible for deamination of cytosine
b) It is responsible for deamination of uracil
c) It is responsible for removal of uracil
d) It is responsible for removal of cytosine
12. DpnI cuts ________ strands.
1. Cloning vectors designed for the purpose of synthesis of RNA and proteins are known as:
a) Cloning vectors
b) RNA vectors
c) Bacteriophage vectors
d) Expression vectors
2. For studying processes such as splicing and cleavage, RNA is required. Choose the correct statement for this.
a) A mixture of different types of RNA is required
b) Two types of RNA are required
c) A few contaminating proteins are required
d) Sodium hydroxide is required
3. RNA can be synthesized by using vector. A vector with _______ is used and further through ________ RNA is isolated.
a) origin of replication, translation
b) promoter, transcription
c) promoter, translation
d) origin of replication, transcription
4. Isolation of RNA can be carried out easily from bacterial cells. Is the given statement true or false?
5. Promoters are generally used after isolation from:
a) bacteriophage T7
b) bacteriophage SP6
c) baceriophage Mu
d) both bacteriophage T7 and SP6
6. By selecting the appropriate polymerase to activate the promoter, ________ can be carried out _______
a) transcription, regardless of orientation
b) transcription, only in one orientation
c) translation, regardless of orientation
c) translation, only in one orientation
7. Guanylyl transferase and GTP are used for?
c) Capping of the message
8. Capping can be introduced by the use of cap analogue. Which of the statement is true?
a) Cap analogue can be introduced at the end of the transcript
b) Cap analogue can be introduced at the start of the transcript
c) Cap analogue can be introduced anywhere in the transcript
d) Cap analogue can be introduced both at the end and starting of the transcript
9. If transcription should not be carried out beyond the insert in the vector, then it should be linearized. Is the given statement true or false?
10. If the cells containing plasmids are infected with helper phage, which type of DNA can be produced, packaged and secreted into the medium?
a) Single stranded DNA
b) Double stranded DNA
c) Both single and double stranded DNA
d) Circular DNA