| I: | A is 3’-5’ direction. |
| II: | B is hydrogen bond. |
| III: | C is phosphodiester bond. |
| 1. | a substituted pyrimidine found only in DNA |
| 2. | a nucleoside monophosphate found only in DNA |
| 3. | a nucleoside found in DNA |
| 4. | a nucleotide formed by chemical modifications in a RNA nucleotide |
| 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. | Maurice Wilkins and Rosalind Franklin |
| 2. | Beadle and Tatum |
| 3. | Temin and Baltimore |
| 4. | Avery–MacLeod–McCarty |
| 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). |
| 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. | 100 | 2. | 130 |
| 3. | 260 | 4. | 300 |
| Assertion (A): | The distance between a bp in a B-DNA helix is approximately 0.34 nm. |
| Reason (R): | The pitch of the B-DNA helix is 3.4 nm and there are roughly 10 bp in each turn. |
| 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). |
| Assertion (A): | Retroviruses are one known exception to the central dogma in molecular biology as proposed by Francis Crick. |
| Reason (R): | In retroviruses a sequence of nucleotides is copied from an RNA template during the synthesis of a molecule of DNA. |
| 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). |