| Statement I: | In the Watson-Crick model of DNA, the two strands of polynucleotides run parallel to each other. |
| Statement II: | The nitrogen bases in the DNA double helix are projected perpendicular to the sugar-phosphate backbone and face inside. |
| 1. | Statement I is correct; Statement II is correct |
| 2. | Statement I is correct; Statement II is incorrect |
| 3. | Statement I is incorrect; Statement II is correct |
| 4. | Statement I is incorrect; Statement II is incorrect |
All of the following are nucleosides, except:
| 1. | Adenosine | 2. | Cytosine |
| 3. | Guanosine | 4. | Uridine |