| Date | May 2010 | Marks available | 3 | Reference code | 10M.3.hl.TZ2.B6 |
| Level | HL | Paper | 3 | Time zone | TZ2 |
| Command term | Distinguish | Question number | B6 | Adapted from | N/A |
Question
The nucleic acids, RNA and DNA, are polymers which are formed from nucleotides. Distinguish between the structures of RNA and DNA.
Markscheme
DNA is double-strand nucleic acid / RNA is single-strand nucleic acid;
DNA (base) is thymine / RNA (base) is uracil;
DNA has deoxyribose as pentose sugar / RNA has ribose;
Accept suitable diagrams.
Examiners report
Most candidates were capable of describing all three differences between RNA and DNA. Candidates must be aware that they should use the names of bases not just what they think is an acceptable symbol such as U or T but rather uracil or thymine.
