This question was the least popular question in this section and many candidates avoided it. Those who
attempted it did not do very well, manifesting candidates' aversion for genetics. Some candidates
however had very high scores on the question.
Most candidates performed fairly well on the defmition of terms but did not do well in the genetic
diagram. They would not correctly express the genotypes of the parents and so this affected the results. .
Some candidates wrote the genotypes of the parents as Tt and IT rather than XBy and XBXb• The
expected answers include:
Parental Phenotype Normal Carrier
Male X Female
Parental genotype XBy X XBXb
F 1 Phenotype Normal normal
Carrier colour blind
female male female male
Most candidates could properly outline Larmack's theory of evolution but some candidates omitted to
state that new characters acquired are passed on to offspring which gives rise to new species.