Regulation of lac operon by repressor is referred to as ..............
Nagative regulation
Both (1) and (2)
Positive regulation
DNA is acidic due to .......
Which of the following amino acid is coded by 3 codons?
The back bone of RNA is consists of which of the following sugar
Maltose
Sucrose
Ribose
Deoxyribose
A DNA nucleotide chain has A G C T T C G A sequence the nucleotide sequence of other chain would be
The minimum requirement for mutation is
Which of the following enzyme is used to join DNA fragments?
The promoter site and the terminator site for transcription are located at
3' (downstream) end and 5' (upstream) end, respectively of the transcription unit
3' (upstream) end and 5' (downstream) end, respectively of the transcription unit
Transcription begins when one of the following enzymes binds to promotor site.
In the genetic code dictionary how many codons are used to code for all the 20 essential amino-acids?
What is the basis for the difference in the synthesis of the leading and lagging strand of DNA molecules?
0/1
DNA ligase works only in the 3' _ 5' direction.
Helicases and single-strand binding proteins that work at the 5' end
DNA polymerase can join new nucleotides only to the 3' end of the growing stand.
Origin of replication occurs only at the 5' end of the moleecules
Genetic code determines the
Enhancing photosynthesis in desert plant
Regulation of plant hormones
Method of DNA replication in which two strands of DNA separates and synthesize new strands?
Which is not the step of translation?
DNA polymerase is needed for ......
the following pairs is not correctly matched?Which of
Recombinant DNA - DNA forming by union of segments of DNA from different sources
r-RNA - RNA molecules found in ribosomes
Purines - Nitrogenous bases Cytosine, Thymine and Uracil
ATP - The principal energy carrying compound inthe cell
E. coli ell grown on 15N medium are transferred to 14N medium and allowed to grow for two generations. DNA extracted from these cells is ultracentrifuged in a cesium chloride density gradient. What density distribution of DNA would you expect in this experiment?
One high and one intermediate density band
One low and one intermediate density band
One intermediate density band
One high and one low density band
A Sequence of three consecutiue bases in a t - RNA molecule which Specifically binds to a complementary codon sequence in m - RNA is known as ............
Non - sense codons take part in
Formation of unspecified aminoacids
Terminating gene controlled protein synthesis
Releasing t-RNA from polynucleotide chain
Conversion of sense DNA in to non-sense one
Assertion: DNA is cut into Sections by using restriction endonucleases ---Reason: Ligase used to join DNA nucleotides
If Assertion is True but the Reason is False
If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
If both Assertion & Reason are false
If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
What does a gene consist of?
A functional unit in synthesis of protein is
Assertion: Catching criminals could become easier and quicker using DNA fingerprints ---Reason: The process begins with blood or cell sample from which DNA is extracted
If Assertion is True but the Reason is False
If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
If both Assertion & Reason are false
Genetic code was deciphered by chemically synthesizing the trinucleotides by
Beadle & Tatum
Waston & Crick
Briggs & King
Functioning of structural genes is controlled by ................
Cluster of structural genes with related function
Protein that accelerates gene expression
Gene that switched other genes on or off
Protein that suppresses gene expression
Termination of chain growth in protein synthesis is brought about by ................
Whose experiments cracked the DNA and discovered unequivocally that a genetic code is a ''triplet''
Semi conservative replication of A was first demonstrated in
Control of gene expression takes place at the level of
What does ''lac'' refer to, in what we call the lac operon?
DNA polymerase and ligase
The following ratio is generally constant for a given species
T + C / G+ A
A + G / C + T
G + C / A + T
Heat killed pathogenic cells and live non pathogenic cells are mixed and injected into Mice the result would be
Mice die without developing disease
50% mice develop discease and die
Mice develop disease and die
Assertion: Lac operation is an inducible system ----Reason: Transcription occurs in the presence of lactose
If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
If both Assertion & Reason are false
If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
If Assertion is True but the Reason is False
Similarity in DNA and RNA is ............
0/1
In which of the following DNA directly involved?
mRNA molecule is produced by
Semionservation replication of DNA was given by ...........
Avery, McCarty and Mactleod
Messelson and Stahi
Watson and Crick
Betason and punnett
Hershey and Chase experiment with bacteriophage showed that
DNA contains radioactive sulphur
Protein gets into the bacterial cells
Viruses undergo transformation
DNA is the genetic material
Which of the following is not a pyrimidine base?
Genetic mutations occur in
Assertion: Normally the genetic code is degenerate ---Reason: One amino acid is coded by more than one codon
If both Assertion & Reason are false
If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
If Assertion is True but the Reason is False
If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
The approximate number of genes contained in the genome of Kalpana Chawla was
Assertion: Helicase is called unwindase ---Reason: DNA helix uncoils and splits into single strands by breaking of hydrogen bonds between complementary bases
If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
If both Assertion & Reason are false
If Assertion is True but the Reason is False
Measelson and Stahl's experiment proved
Semi-conservative nature of DNA replication
DNA is the genetic material
Assertion: There occur 64 codons in dictionary of genetic code---Reason:Genetic code is quadraplete
If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
If both Assertion & Reason are false
If Assertion is True but the Reason is False
If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
A gene containing multiple exons and at least one intron is termed as ...........
0/1
Substance common in DNA molecules is made up of
Hexose Sugar
Histamine
Thymine
Amino acid sequence in protein synthesis is decided by the sequence of
Which one of the following makes use of RNA template to synthesize DNA
DNA dependant RNA polymerase
What does operon contain?
Regulator gene + structural gene structural gene
Operator gene + structural gene
Regulator gene + promotor gene + operator gene + structural gene
Regulator gene +promotor gene
The direction of DNA replication is ............
From 5' end towards 3' end
Carboxy terminus to amino terminus
From 3' end towards 5' end
Amino terminus to carboxy terminus
Who supported Griffith effect by molecular explanation?
Avery, Mc Carty and Macleod
Ribosomal RNA is actively synthesized by .....
Which of the following statements about DNA replication is not correct?
Unwinding of DNA molecule occurs as hydrogen bonds break.
Replication occurs as each base is paired with another exactly like it
Complementary base pairs are held together with hydrogen bonds
Process is known as semi conservative replication one old strand is conserved in the new molecule.
Termination of polypeptide chain is brought about by
One - gene - one enzyme hypothesis was proposed by ..................
Synthesis of nucleic acids always takes place in
The enzyme amino acyl t-RNA -synthetase facilitates
Joining two neighbouring amino on ribosomes
Adoption of amino acids by a t-RNA molecule
Insertion of amino acyl t-RNA into the ribosome sites.
Transfer of amino acyl t-RNA from the ribosomal 'A' site to 'P' site
Genetic information is carried by the long chain molecules which are made up of ............
Chargaff's rule is given as
Codons constitute genetic code because
There was 64 types of amino acid
Assertion: Mutation results in changes in the genotype and the phenotype of an organism ---Reason: Mutation is a phenomenon, which results in alternation of DNA sequences
If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
If both Assertion & Reason are false
If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
If Assertion is True but the Reason is False
Assertion: Formation of Lagging strand is slow ---Reason: Formation of lagging strand begins bit later than that of leading strand
If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
If Assertion is True but the Reason is False
If both Assertion & Reason are false
If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
State the anticodon of initiation codon of protein synthesis
Bond between phosphate and sugar in a nucleotide is ..........
A Sequence of how many nucleotides in messager RNA makes a codon for an amino acid?
During transcription if the nucleotide sequence of the DNA strand that is being coded is ATACG then the nucleotide sequence in the m RNA would be
Assertion: Operon concept was given by Hershey and chase---Reason: Separation of DNA fragments are done by centrifugation technique
If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
If both Assertion & Reason are false
If Assertion is True but the Reason is False
The first codon to be deciphered was ........... which codes for .............. .
Nucleoside is .................
Phosphoric acid + Sugar + base
DNA acts as a template for synthesis of ..........
Prokaryotic genetic system contains:
Which of the following is not associated with HGP?
Cloning vectors BAC & YAC
The lac opern consists of ...............
Three regulrtory genes three structural genes
Four regulatory genes only
Two regulatory genes and three structural genes
One regulatory gene and three structural genes
The first genetic material could be
DNA
Carbohydrates
Protein
t-RNA attach to larger sub unit of ribosome with the help of which loop?
Assertion; DNA is a chemically and structurally more stable. ---Reason: DNA have no catalytic properties.
If both Assertion & Reason are false
If Assertion is True but the Reason is False
If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
Which of the following is the correct sequence of event with reference to the central dogma?
Transcription, Replication, Translation
Duplication, Translation, Transcription
Transcription, Translation, Replication
Replication, Transcription, Translation
Okazaki fragments are joined by enzyme
The code AUG stands for ...............
Which of the following enzyme is not produced by E.coli during lactose catabolism?
Thio glactoside translacetylase
Which of the following statements is not true about DNA replication in eukaryotes?
Replication occurs at about 1 million base pairs per minute.
Replication is bidirectional from the origins.
There are numerous different bacterial chromosomes, with replication ocurring in each at the same time.
Replication begins at a single origin of replication.
Multiplication of DNA is called as
Which of the following enzymes can detect and correct the wrong inserted base during DNA replication?
Number of H - bonds between guanine and cytosine are .......
The total number f nitrogenous bases in human genome is estimated to be about
Genetic information are transferred from nucleus to cytoplasm of cell through
Which of the following enzymes help in the process of formation of phosphor di-ester bond during reverse transcription?
DNA - dependant DNA polymerase
RNA - dependant DNA polymerase
DNA - dependant RNA polymerase
RNA - dependant RNA polymerase
Pneumococcus experiment proved that
RNA may sometimes control a production of DNA and protein
Bacteria undergo binary fission
Bacteria do not reproduce asexually
Which of the following is used in DNA multiplication?
Method by which information reaches from DNA and RNA is .......
Translation
Transcription
Transformation
What is the nature of the 2 strands of a DNA duplex?
Dissimilar & non complimentary
Anti parallel & non complimentary
Identical & Complimentary
Ant parallel & Complimentary
Select the correct sequence of following in DNA replication
Helicase - DNA polymerase - Topoisomerase - Single stranded binding proteins
Single stranded binding proteins - Helicase - Topoisomerase - DNA polymerase
Helicase - Topoisomerase -DNA polymerase - Single stranded binding proteins
Helicase - single stranded binding proteins -Topoisomerase - DNA polymerase
Which of the following causes mutation
DNA and RNA are similar with respect to
Thymine as a nitrogen base
The same sequence of nucleotides for the amino acid phenyl alanine
A single-stranded helix shape
Nucleotide containing sugars, nitrogen bases and phosphates
DNA replication in eukaryotes is ............
Bidirectional with many origin
Unidirectional with single origin
Bidirectional with single origin
Unidirectional with many origin
Anti parallel strand in DNA is due to
The strand of DNA, which does not code for anything is referred to as ............
Antisense strand
Coding strand
Template stand
Protein synthesis is an animal cell occurs
On ribosomes present in cytoplasm as well as in mitochondria
Only on ribosomes attached to the nuclear envelop and endoplasmic reticulum
Only on the ribosomes present in cytosol
On ribosomes present in the nucleolus as well as in cytoplasm
Assertion: In DNA fingerprinting, after hybridization with VNTR probe, the auto radiogram gives many bands of different sizes. --- Reason: It differs from individual to individual in a population except fraternal twins.
If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
If both Assertion & Reason are false
If Assertion is True but the Reason is False
By which bonds the purine & pyrimidine pairs of complementary strands of DNA held together?
H - bonds
O - bonds
C - bonds
Three nucleotides
Two nucleotides
Single nucleotide
Which is not correct regarding the activity of helicase during DNA replication?
Stabilizes single strands
Southern blotting is used for the identification of
RNA
DNA
All the above
Protein
The amino acid attaches to the tRNA at it's
S' - end
DHU loop
Anti codon site
3' - end
The net electric charge on DNA and histones is ........
Translation is the process in which ...........
Protein is formed from RNA
RNA is formed on DNA template
DNA is formed on RNA template
DNA is formed on DNA template
DNA is not present in ..........
Bacteriophage
Chioroplast
Mitochondria
Both dexoyribose and ribose belong to a class of sugars called as .....
Nitrogen base, pentose sugar
Nitrogen base, trioses and phoshoric acid
Nitrogen base, pentose sugar and phosphoric acid
Nitrogen, Hexose sugar and phosphoric acid
Poly some is formed by ..............
Many ribosomes attached to a strand of endoplasmic reticulum
A ribosome with several sudunits
Several ribosomes attached to a single m RNA
Ribosomes attached to each other in a linear arrangement
Name the enzymes needed for lactose catabolism in E.coli?
B - galactosidasee Lactase, transacetylase
B - galactosidase, permease transacetylase
Lactase, permease, transacetylase
B - galactosidase, lactase, permease
Semi conservative DNA replication using 15 N was demonstrated by
What is called Griffith effect?
The information from RNA to DNA are transferred by which process?
Replication
Translation
Transcription
Okazaki fragments are synthesized on
Leading and Lagging strands
Lagging strands of DNA only
Complemetary DNA strand
Leading strands of DNA only
Double helix model of DNA is proposed by
In a transcription unit promotor is said to be located towards
5' end of structural gene
3' end of template strand
3' end of structural gene
5' end of template strand
Enzymes needed for formation of replication fork is ..............
RNA polymerase and DNA polymerase I
t - RNA attaches amino acid at it's
In some viruses, DNA is synthesised by using RNA as template. Such a DNA is called as ........
DNA acts as a template for synthesis of .........
The change of chromosomal parts between non homologous pairs of chromosome is ...........
DNA Replication occurs at .......
Intiation codon of protein synthesis (in eukaryotes) is ........
Which one of the following triplet codes, is correctly matched with its specificity for an amino acid in protein synthesis or as 'start' or 'stop' codon?
Who proved DNA as a genetic material
Which is the smallest RNA?
One of the following is true with respect to AUG
It is also an initiation codon
It codes for methionine in both prokaryotes and eukaryotes
It codes for methionine only
The enzyme involved in transcription is ............
DNA polymerase I
DNA polymerase II
RNA polymerase
Correct sequence of code transfer during polypeptide formation is .......
m RNA, tRNA, DNA and amino acids
DNA, mRNA, tRNA and amino acids
Assertion: Base pairing between purine and pyrimidines allows uniforms distance between two strands of the helix. ---Reason: Number of hydrogen bonds between pairing bases are constant.
If Assertion is True but the Reason is False
If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
If both Assertion & Reason are false
If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
synthesis of DNA occurs in one strand, because
DNA ligase has to have a role
DNA molecule being synthesised is very long
It is a more efficient process
DNA dependent DNA polymerase catalyses polymerisation only in one direction (5' -->3')
Assertion: Mutations effect protein structure and functions ---Reason: Only one changed insertion of one amino acid
If both Assertion & Reason are false
If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
If Assertion is True but the Reason is False
Aminoacids lysine serine and arginine are coded by how many codons?
When lactose is present in the culture medium:
Repressor is able to bind to the operator
Repressor is unable to bind to the operator
Transcription of lac y, lac z, lac a genes occurs.
Both (a) and (b) are correct.
Which step is not correct in DNA finger printing?
Digestion of DNA by DNA ligase enzyme
Separation of DNA by elecrophoresis
Hybridisation using labelled VNTR probe
Nucleotide arrangement in A can be seen by
Assertion: Replication and transcription occur in the nucleus but translation occurs in the cytoplasm ---Reason: Transcription and translation are unidirectional
If both Assertion & Reason are false
If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion
If Assertion is True but the Reason is False
If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion
If one strand of DNA has the nitrogenous base sequence as ATCTG, What would be the complementary RNA strand sequence
Select correct match with respect to lac-operon model
Active repressor + corepressor = Inactive repressor
Inactive repressor + corepressor = Active repressor
Inactive repressor + inducer = Active repressor
Active represser + inducer = Inactive repressor
DNA replication in lagging strand of the eukaryotes organisms is .......
Sami conservative but continuous
Conservative and continuous
Conservative and semi - discontinuous
Semi conservative but discontinuous