AP Lab 7: Genetics of
Drosophila (fruit flies)
Carolina
Purpose

Use fruit flies to do genetic crosses.

Learn to determine the sex of fruit flies
and recognize contrasting phenotypes.

Collect data from F1 and F2 generations
and analyze the results of a
monohybrid, dihybrid, or sex-linked
cross.
Activity A

In part A you will learn to:

observe wild-type flies

recognize male and female flies

compare the mutant phenotypes with the
wild type.

http://www.phschool.com/science/biology_
place/labbench/index.html
Procedure

Anesthetizing flies will be demonstrated.

Flies will be placed in petri dishes to be
observed.

Draw and document important differences
between phenotypes of:

Males and females
Wild types and mutants

Procedure

After you have observed the flies, return
them to the correctly labeled morgue.

Make sure that if flies begin moving they
are returned to the morgue quickly.

The anesthetizing agent lasts
approximately 50 min.
Activity B

Setting up vials:

Obtain one vial and add 1 level measure
cup of Formula 4-24 to the vial.

Add 1 level measure cup of tap water to
the vial.

After it solidifies, sprinkle 4-7 grains of
yeast to the culture
Procedure

Setting up F1 cross:

Record the code for the cross that you were
given.

Collect 5-6 male/female pairs. (10-12 flies total)

Using Table 2: F1 Data, record sex and
phenotypes for the flies you were given.

Place these flies in your vial and label with
information from the lab.

Return remaining flies to the morgue.
Feedback