| Date | May 2011 | Marks available | 1 | Reference code | 11M.1.SL.TZ2.24 |
| Level | Standard level | Paper | Paper 1 | Time zone | Time zone 2 |
| Command term | Question number | 24 | Adapted from | N/A |
Question
A parent organism of unknown genotype is mated in a test cross. Half of the offspring have the same phenotype as the parent. What can be concluded from this result?
A. The parent of unknown genotype is heterozygous.
B. The parent of unknown genotype is homozygous dominant.
C. The parent of unknown genotype is homozygous recessive.
D. The parent of known genotype is heterozygous.
Markscheme
A
Examiners report
N/A
Syllabus sections
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