When compared to DNA, in RNA:
I: every nucleotide residue has an additional –OH group present at 3'-position in the ribose.
II: 5-methyl uracil is found instead of thymine.
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:  DNA vs RNA as Genetic Material |
From NCERT
Please attempt this question first.
Hints
Please attempt this question first.

In 1953, James Watson and Francis Crick, proposed a very simple but famous Double Helix model for the structure of DNA, based on the X-ray diffraction data produced by:
1. Maurice Wilkins and Rosalind Franklin
2. Beadle and Tatum
3. Temin and Baltimore
4. Avery–MacLeod–McCarty
Subtopic:  DNA Double Helix |
 94%
From NCERT
Please attempt this question first.
Hints
Please attempt this question first.

“For a double stranded DNA, the ratios between Adenine and Thymine and Guanine and Cytosine are constant and equals one” – this statement is known as:
1. Central dogma of molecular biology
2. Chargaff’s rule
3. Tetra-nucelotide hypothesis by Levene
4. Genetic equilibrium
Subtopic:  DNA Double Helix |
 95%
From NCERT
Please attempt this question first.
Hints
Please attempt this question first.

advertisementadvertisement

Consider the given two statements:
Assertion (A): If the sequence of bases in one strand of the dsDNA molecule is known then the sequence in other strand can be predicted.
Reason (R): The base pairing in a dsDNA molecule is complementary to each other.
 
1. Both (A) and (R) are True but (R) does not correctly explain (A).
2. (A) is True but (R) is False.
3. (A) is False but (R) is True.
4. Both (A) and (R) are True and (R) correctly explains (A).
Subtopic:  DNA Double Helix |
 86%
From NCERT
Please attempt this question first.
Hints
Please attempt this question first.

How many of the given features will be true for of the double-helix structure of DNA?
I: It is made of two polynucleotide chains
II: The backbone is constituted by sugar-phosphate
III: The two chains have anti-parallel polarity.
IV: The bases in two strands are paired through hydrogen bonds (H-bonds) forming base pairs (bp)
1. 1
2. 2
3. 3
4. 4
Subtopic:  DNA Double Helix |
 92%
From NCERT
Please attempt this question first.
Hints
Please attempt this question first.

A hypothetical dsDNA of 100 bp length molecule was found to be composed of 40 Adenine residues. The total number of hydrogen bonds in all base pairs of this molecule is expected to be:
1. 100
2. 130
3. 260
4. 300
Subtopic:  DNA Double Helix |
 80%
Please attempt this question first.
Hints
Please attempt this question first.

advertisementadvertisement

Consider the given two statements:
Assertion: The distance between a bp in a B-DNA helix is approximately 0.34 nm.
Reason: The pitch of the B-DNA helix is 3.4 nm and there are roughly 10 bp in each turn.
 
1. Both Assertion and Reason are true but Reason does not correctly explain the Assertion.
2. Assertion is true but Reason is False.
3. Assertion is false but Reason is True.
4. Both Assertion and Reason are true and Reason correctly explains the Assertion.
Subtopic:  DNA Double Helix |
 62%
From NCERT
Please attempt this question first.
Hints
Please attempt this question first.

Consider the given two statements:
Assertion: Retroviruses are one known exception to the central dogma in molecular biology as proposed by Francis Crick.
Reason: In retroviruses a sequence of nucleotides is copied from an RNA template during the synthesis of a molecule of DNA.
 
1. Both Assertion and Reason are true but Reason does not correctly explain the Assertion.
2. Assertion is true but Reason is False.
3. Assertion is false but Reason is True.
4. Both Assertion and Reason are true and Reason correctly explains the Assertion.
Subtopic:  The DNA |
 72%
From NCERT
Please attempt this question first.
Hints
Please attempt this question first.

Nucleosome:
I: is formed by the wrapping of negatively charged DNA around the negatively charged histone octamer.
II: typically contains 200 bp of DNA helix.
III: constitutes the repeating unit of a structure in nucleus called chromatin.
IV: is seen as ‘beads-on-string’ structure when viewed under electron microscope (EM).
1. Only I, II and III are correct
2. Only I, III and IV are correct
3. Only II, III and IV are correct
4. I, II, III and IV are correct
Subtopic:  DNA Packaging |
 84%
From NCERT
Please attempt this question first.
Hints
Please attempt this question first.

advertisementadvertisement

Consider the given two statements:
Assertion (A): Euchromatin is said to be transcriptionally active chromatin, whereas heterochromatin is inactive.
Reason (R): Light stained region of chromatin is euchromatin and dark stained region is heterochromatin.
 
1. Both (A) and (R) are True but (R) does not correctly explain (A).
2. (A) is True but (R) is False.
3. (A) is False but (R) is True.
4. Both (A) and (R) are True and (R) correctly explains (A).
Subtopic:  The DNA |
 72%
From NCERT
Please attempt this question first.
Hints
Please attempt this question first.