| Date | May 2011 | Marks available | 1 | Reference code | 11M.1.SL.TZ2.18 |
| Level | Standard level | Paper | Paper 1 | Time zone | Time zone 2 |
| Command term | Question number | 18 | Adapted from | N/A |
Question
A human cell has between 20 000 and 25 000 genes whereas an E. coli cell has approximately 4000 genes. Which of the following statements is true?
A. The human genome is larger than the E. coli genome.
B. There are more genes on each human chromosome than on the E. coli chromosome.
C. The human cell and the E. coli cell produce approximately the same variety of proteins.
D. The DNA in both organisms is associated with histones (proteins).
Markscheme
A
Examiners report
This question was well answered by candidates though some teachers felt that they would find it difficult.
