| Date | May 2010 | Marks available | 1 | Reference code | 10M.1.SL.TZ1.15 |
| Level | Standard level | Paper | Paper 1 | Time zone | Time zone 1 |
| Command term | State | Question number | 15 | Adapted from | N/A |
Question
What are homologous chromosomes?
A. Identical chromosomes
B. Non-identical chromosomes with different genes
C. Non-identical chromosomes with the same genes in the same sequence but not necessarily the same alleles
D. Non-identical chromosomes with the same genes in a different sequence and not necessarily the same alleles
Markscheme
C
Examiners report
There was a complaint in the G2 that this question was tricky and confusing. This is not the intention. As a matter of fact, this question turned out to be a very good discriminator and most good candidates chose the correct answer C. Many other candidates went for answer A, showing they did not quite understand the concept of homologous chromosomes
