DrosophiLab is a brilliant, free and downloadable piece of software that allows students and teachers to edit fruit flies and carry out crosses. The teacher can use the chromosome editor to set up parent flies of any genotype and there are 20 genes and traits represented, on four chromosomes. This allows for simple monohybrid crosses, sex-linkage, gene linkage and many other combinations – so the problems you set can be differentiated by level. There is also a password-protected teacher setting, to restrict students’ access to results tables and chromosome maps (so they have to work it out for themselves!).
Here are our class resources:
Fly files in this folder: http://www.box.net/shared/dy326rb01d
Chi-Calc (Chi-squared calculator, .xlsx)
How to catch and observe Drosophila:
And this is how you tell the sexes apart:
When trying to observe the flies for real, think about the following questions:
– How are you ensuring ethical treatment of the animals?
– How long would it take to determine the phenotypes of the number of flies you have set for your investigations?
– What difficulties do you encounter when observing the flies?
– What are the limitations or sources of error that might affect the reliability of your results?
Why are fruit flies so important in science?
Science loves fruit flies, and there was even a fruit fly Nobel awarded in 1995 for studies in embryonic development. This links neatly to the assessment statements regarding the differentiation of cells through expression of different genes.
Fruit fly cells are relatively easily observed, and Drosophila makes for an ideal model organism for Mendelian genetics as it has a short life cycle, reproduces quickly and is easily phenotyped.
Drosophila buscki from Journal of Endocrinology
Fruit fly graphic and DrosophiLab banner from DrosophiLab