Given below are statements on the structure of the DNA double helix.
1. The helix generally is wound clockwise.
2. purines and pyrimidines are paired by different numbers of hydrogen bonds.
3. The two strands run in parallel polarity. 
4. The sugar in the DNA backbone is pentose sugar.
Which of the above statement/s is/are  NOT TRUE?
1. Only 1.
2. Only 2. 
3. Only 3.
4. Only 2 and 4.
  

Subtopic:  DNA Double Helix |
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The fact that a purine base always pairs through hydrogen bonds with a pyrimidine base in the DNA double helix leads to:
1. the anti-parallel nature.
2. the semi-conservative nature.
3. uniform width throughout the DNA.
4. uniform length in all DNA. 
Subtopic:  DNA Double Helix |
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In the representation of the Central Dogma of Molecular Biology given below, identify P, Q and R.

1. P: ligase; Q: histone; R: polymerase
2. P: translation; Q: mRNA; R: transcription
3. P: splicing; Q: mRNA; R: capping 
4. P: transcription: Q: mRNA; R: transcription 
Subtopic:  DNA Double Helix |
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The average Guanina content in yeast is found to be \(18 \%\).
Which of the following represents the nitrogenous base content percentages correctly from the above data?
1. \(\text { A: } 18 \% \text {; T: } 18 \% \text {; C: } 36 \%\)
2. \(\text { A: } 36 \% \text {; T: } 32 \% ; \text { C: } 32 \%\)
3. \(\text { A: } 32 \% \text {; T: } 32 \% \text {; C: } 18 \%\)
4. \(\text { A: 18%; T: 18%; C: 18%}\)
Subtopic:  The DNA |
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Consider the following genetic code:
Which among the following would cause a frameshift mutation?

1. substitution of A by C in codon 2
2. insertion of G after C in codon 4
3. insertion of GCU after C in codon 6
4. deletion of codon 3, GAG
Subtopic:  Genetic Code: III |
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Assertion (A):  RNA polymerases are able to catalyse all three steps of transcription.
Reason (R):  RNA polymerase contains an initiation factor and a termination factor in them.
 
1.  Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. (A) is false but (R) is true.
Subtopic:  Transcription: I |
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Which among the following statements about the exons is TRUE?
1. They are stop codons.
2. They are start codons. 
3. They are coding sequences.
4. They are intervening sequences. 
Subtopic:  Transcription: I |
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Study the given diagrammatic representation of Griffith's experiment to demonstrate the transformation in bacteria.

Select the option which is incorrectly representing the experiment:
1. (i) and (ii)
2. (ii) and (iii)
3. (iii) and (iv)
4. (ii) and (iv) 
Subtopic:  Search for Genetic Material |
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Assertion (A):  Primary transcripts in eukaryotes are non-functional. 
Reason (R):  Methyl guanosine triphosphate is attached to 5' -end of hnRNA.
 
1.  Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. (A) is false but (R) is true.
Subtopic:  Transcription: IV |
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The length of DNA is:
I: usually defined as number of nucleotides (or a pair of nucleotide referred to as base pairs) present in it.
II: is the characteristic of an organism.
1. Only I is correct
2. Only II is correct
3. Both I and II are correct
4. Both I and II are incorrect
Subtopic:  The DNA |
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