(a(i))[1]
What type of variation is shown in Fig. 2.2?
(a(ii))[3]
Suggest and explain how genes and the environment contribute to differences in IPD in humans.
(b(i))[3]
State the term used for a gene, such as $\textit{PAX3}$, that regulates the expression of other genes, and suggest how the $\textit{PAX3}$ protein regulates the expression of other genes.
(b(ii))[5]
Describe how microarray analysis could be used to find the genes activated by $\textit{PAX3}$ in embryonic cells.
(b(iii))[3]
Suggest how understanding the $\textit{PAX3}$ gene helps scientists explain why humans and chimpanzees differ greatly in facial structure, despite having very similar DNA.