| Date | May 2011 | Marks available | 1 | Reference code | 11M.1.HL.TZ1.12 |
| Level | Higher level | Paper | Paper 1 | Time zone | Time zone 1 |
| Command term | Question number | 12 | Adapted from | N/A |
Question
Which of the following statements about homologous chromosomes is correct?
A. Each gene is at the same locus on both chromosomes.
B. They are two identical copies of a parent chromosome which are attached to one another at the centromere.
C. They always produce identical phenotypes.
D. They are chromosomes that have identical genes and alleles.
Markscheme
A
Examiners report
This question discriminated very well. However, many choose either B or D, both of which were incorrect showing a lack of understanding of what homologous chromosomes are.
