Question 1 :
Which one of the following is the complementary sequence for the DNA with $5'$-CGTACTA-$3'$.
Question 3 :
<i></i><i></i>The experimental system used in studies of the discovery ofreplication of DNA has been<br>
Question 4 :
The two strands of double helix of DNA are linked together by hydrogen bonds between
Question 7 :
The number of purines in a segment of DNA molecule is 68. What will be the number of pyrimdines in this segment ?
Question 8 :
Choose the correct answer from the alternatives given :<br>Ifthe sequence of nitrogen bases of the coding strand of DNA in a transcriptionunit is: 5 - A T G A AT G - 3, the sequence of bases in its RNA transcriptwould be
Question 9 :
In  a dsDNA number of phosphodiester bonds are $3250$, then find the number of base pairs.
Question 11 :
What is the length of human DNA containing $6.6\times10^9$ bp nitrogen bases?
Question 14 :
Which of the following is the co-factor for origin of life from pre-RNA?
Question 18 :
In the double helix model of DNA, what would bethe distance between two consecutive base pairs?
Question 20 :
Whichof the following biologists has been dubbed as the architect of molecular biology?
Question 21 :
Watson and Crick were awarded Nobel Prize for their finding of
Question 24 :
Which one of the following combinations is found in DNA ?
Question 25 :
According to Watson-Crick model, hydrogen bonding in a double-stranded DNA occurs between.
Question 33 :
1.38 milimeter DNA is present in E. coli. How many base pair will be present in it?
Question 36 :
During Meselson and Stahl's experiments, heavy DNA wasdistinguished from normal DNA by which type of centrifugation?<br>
Question 37 :
In a DNA molecule, the phosphate group is attached to ____carbon of the sugar residue of its own nucleotide and _____ carbon of the sugar residue of the next nucleotide by ____bonds.<br/>
Question 39 :
If there are 120 adenine molecules in a B-DNA<i> </i>double helical structure showing 20 coils, what is the number of pyrimidine nucleotides forming three hydrogen bonds in it?
Question 40 :
A sample of DNA is found to have the base composition (mole ratio) of A = 40, T = 22, G = 21 and C = 17. This suggests
Question 41 :
Analysis of DNA of an organism revealed the following characters. Mark the option that is not likely to be true if the organism is a cat.
Question 42 :
Which of the following is true of RNA, but not DNA?
Question 43 :
The double helix model of Watson and Crick is known as<br>
Question 44 :
A double stranded DNA having 100,000 bp will have a length of
Question 47 :
Choose the correct answer from the alternatives given :<br>Ina DNA strand the nucleotides are linked together by
Question 48 :
In the double helix model of DNA as proposed by Watson and Crick, each base pair is how far from the next base pair?
Question 50 :
Melting temperature for double stranded molecules are converted into single strandedmolecules. Which one of the following DNA will have the highest melting temperature?<br>
Question 57 :
Hypothesis of ''African origin'' of man is based on the study of____________
Question 58 :
Which of the following is an estimated length of linker DNA?
Question 59 :
In one polynucleotide strand of a DNA molecule, the ratio of $A+T/G+C$ is $0.3$. What is the $A+G/T+C$ ratio of the entire DNA molecule?
Question 60 :
If the length of DNA strand is ${ 68A }^{ \circ }$ then, what will be the number of nucleotides present in DNA molecule
Question 61 :
Choose the correct answer from the alternatives given :<br>Watson and Crick (1953) proposed DNA double helix model and won the Nobel Prize; their model of DNA was based on<br><b></b>(i) X-ray diffraction studies of DNA done by Wilkins and Franklin<br>(ii) Chargaffs base equivalence rule<br>(iii) Griffiths transformation experiment<br>(iv) Meselson and Stahls experiment.<br>
Question 63 :
Taylor conducted the experiments to semiconservative mode of chromosome replication on
Question 64 :
Choose the correct answer from the alternatives given :<br>Referto the given steps Of DNA replication.<br>(i)Exposure of DNA strands<br>(ii)Synthesis of RNA primer<br>(iii)Activation of deoxyribonucleotides<br>(iv)Chain formation<br>(v)Base pairing<br>(vi) Proof reading and DNA repair<br>(vii)DNA polymerase attaches at Or site<br>Selectthe correct sequence of DNA replication.<br>
Question 66 :
"It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for genetic material" - This is written by<br/>
Question 67 :
A short length of DNA molecule has 80 thymine and 80 guanine bases. The total number ofnucleotids in the DNA fragment is
Question 68 :
Read the following statements and select the Correct option.<br>(i) Loosely packed and lightly stained region of chromatin are called as heterochrormatin.<br>(ii) Densely packed and dark stained region of chromatin are called as euchromatin.<br>(iii) A typical nucleosome contains 200 bp of DNA helix.<br>
Question 70 :
If percentage of cytosine is 18%, what will be the percentage of adenine?<br/>
Question 71 :
Choose the correct answers from the alternatives given.<br>What is the function of DNA ligase in recombinant technology?
Question 72 :
Choose the correct answer from the alternatives given :<br>Whichof the following phenomena was experimentally proved by Meselson and Stahl?
Question 74 :
Two students are given two different double stranded DNA molecules of equal length. They are asked to denature the DNA molecules by heating. The DNA given to student A has a following composition of base (A : G : T : C :: 35 : 15 : 35 : 15) while that given to student B is (A : G : T:  C :: 12 : 38 : 12 : 38). Which of the following statement is true?<br/>
Question 76 :
Palaeontologists unearthed a human skull during excavation.  A small fragment of the scalp tissue was still attached to it. Only little DNA could be extracted from it. If the genes of the ancient man need to be analysed, the best way of getting sufficient amount of DNA from this extract is <br/>
Question 77 :
Nobel Prize to A. Kornberg and S. Ochoa was given for
Question 81 :
No. of of phosphoester bonds found in one turn of DNA is ____________.
Question 82 :
<i>E. coli</i>, to be replicated, is placed in a medium containing radioactive thymidine for five minutes. Then it is made to replicate in a normal medium. Which of the following observation will be correct ?
Question 83 :
A $340\overset {\circ}{A}$ long segment of DNA molecule has $20$ thymine nitrogenous bases, what will be the number of guanine nitrogen bases in the same segment?
Question 84 :
Transfer of DNA bands from an agarose gel to a nitrocellulose or nylon membrane is referred to as
Question 85 :
Choose the correct answers from the alternatives given :<br>Whichof the following regarding DNA is not true?
Question 89 :
Assertion: Histones are basic proteins of major importance in packaging of eukaryotic DNA. DNA and histones comprise chromatin forming the bulk of eukaryotic chromosome.
Reason: Histones are of five major types: H1, H2A, H2B, H3 and H4.
Question 91 :
In the Watson and Crick model of DNA, the steps of the ladder are composed of
Question 94 :
DNA in the nucleus of rabbit egg is 1.8 picograms, its liver cell will have mass of DNA ______ picograms.
Question 95 :
Out of A-T, G-C pairing, bases of DNA may exist in alternate valency state owing to arrangement called as
Question 96 :
Why does synthesis of DNA proceed only in the $5'$ to $3'$ direction?
Question 99 :
Watson & Crick proposed the model of DNA structures in which of the following years?<br/>
Question 100 :
If the total amount of adenine and thymine in a double-stranded DNA is 45%, the amount of guanine in this DNA will be<br/>
