(a)[3]
In $\textit{Drosophila}$, males have two different sex chromosomes, $X$ and $Y$, just as humans do. Complete the genetic diagram below to show how the results in Table 1.1 may have arisen.
(b(i))[3]
The chi-squared ($\chi^2$) test may be used to examine the results in Table 1.1. The expected ratio of red-eyed females to white-eyed males is $1 : 1$. Complete Table 1.2 and use it to calculate a value for chi-squared ($\chi^2$). The formula is $\chi^2 = \sum \frac{(O - E)^2}{E}$ and $v = n - 1$.
(b(ii))[2]
Use your calculated value of $\chi^2$ and the probability table below to test whether the difference between the observed and expected results is significant.