1. Working with Drosophila
BTEC Applied Science
Unit 18: Genetics
Assignment 3: Inheritance

2. Starter Quiz
For Each question, write down the answer in your notes…

3. Question 1:
Which is the Male fly? B A

4. Question 2
What mutation is this fly displaying?

5. Question 3
Which Mutation is this fly displaying?

6. Question 4:
What would be the ‘phenotype’ of a fly with the following genotype:
vg+vg+ebeb

7. Question 5
What would be the ‘phenotype’ of a fly with the following genotype:
vgvg eb+eb+

8. Question 6
Is this fly male or female?

9. Answers: B Vestigial Wings Ebony body Ebony body, non vestigial wings
Vestigial wings, non-ebony body
Male

10. Lesson Objectives:
1. To know how to handle, anaesthetise and sex drosophila melanogaster (fruit flies) 2. To understand how/why X-Linked inheritance can produce unexpected outcomes in the offspring.

11. Drosophila
Use the Fly Nap to put the flies to sleep (follow instructions given in class)
Empty some flies onto a petri dish. Use a paintbrush to move them around if needed.
Observe the flies using a hand lens or microscope.
Keep a record of the number of male and female flies and note down what their phenotypes are.

12. X – Linked Inheritance
Some alleles are carried on the X-Chromosome. (what do you know about the X chromosome?) We refer to this type of inheritance as ‘X-Linked Inheritance’ or ‘Sex-Linked Inheritance’