1.1. Drosophila melanogaster is a fruit fly and is a useful organism to study patterns of inheritance. Female fruit flies can lay up to 400 eggs, developing into adults between 7 and 14 days. They have simple nutrient requirements.

Using the information provided explain two reasons why Drosophila melanogaster is a useful organism to study patterns of inheritance.

1.2. In Drosophila melanogaster the genes for eye colour and antenna shape are linked.

Explain what this means. 

1.3. Scientists investigated patterns of inheritance of eye colour and antenna shape in fruit flies. They carried out multiple crosses between fruit flies homozygous for both red eyes and bent antennae, and fruit flies homozygous for both white eyes and straight antennae. They found that all of the offspring produced in the F1 generation were heterozygous for both characteristics, having red eyes and bent antennae.

• R represents the dominant allele for red eyes and r represents the recessive allele for white eyes

• B represents the dominant allele for bent antenna and b represents recessive allele for straight antennae

The offspring from the F1 generation were crossed with fruit flies homozygous for both white eyes and straight antennae.

The results of these crosses are shown below in Table 1. 

Table 1

Table 1 shows the number of offspring produced for each phenotype

Explain the results from Table 1.

1.4. To determine if there is a significant difference between the observed results and expected results a statistical test can be used. State which statistical test should be used and explain your reasoning.