Biology 9700 · AS & A Level · Passage of information from parents to offspring
Passage of information from parents to offspring — practice question
The fruit fly, Drosophila melanogaster, has eyes, a striped abdomen, and wings that are longer than its abdomen. A fly with these characteristics is called a ‘wild-type’ fly. Mutation has produced many different forms of these characteristics. Table 6.1 presents diagrams of a wild-type fly and three other flies, each showing one recessive mutation.
(a)[4]
Using appropriate symbols, complete the genetic diagram below.
(b)[1]
State how you would carry out a test cross.
(c)[3]
A cross was made between a fly heterozygous for striped abdomen and long wings and a fly with a black abdomen and short wings. The outcomes are shown in Table 6.2. A chi-squared test ($\chi^2$) was carried out on these data. Complete Table 6.3 and calculate the value of $\chi^2$.
(d)[2]
Table 6.4 displays $\chi^2$ values. Using Table 6.4, explain what conclusions can be drawn from the results of the $\chi^2$ test.
Worked solution & mark scheme
This 10-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Key for 4 genetic symbols” …