Fly Lab
Genetics of
Organisms
Overview
During this lab you will use
this simple powerpoint to
simulate genetic crosses of
Drosophila melanogaster.
Why use the fruit fly?
It has simple food requirements,
occupies little space, is hardy,
has a short lifecycle (12 days),
produces a large number of
organisms, and has many types
of hereditary variations.
The Experiment
You will study a mode of
inheritance using genetic
crosses of flies having one or
two mutations.
Modes of Inheritance
The following modes of inheritance
are commonly studied.
1.Monohybrid
2.Dihybrid
3.Sex-linked
What mode?
To make the experiment
more challenging, you
will not be told the
mode of inheritance,
your job is to determine
the mode of inheritance.
To determine the mode:
•You will analyze data
from genetic crosses.
•You will need to tell
the difference between
males and females.
Examine the flies for future
identification.
Male
Female
Males or Females?
Males are usually smaller than
females.
Males have dark, blunt abdomens,
and females have lighter, pointed
abdomens.
Only males have sex combs, which
are groups of black bristles on the
uppermost joint of the forelegs.
Examine the flies on the following
page:
1.
2.
3.
Look for mutations.
Note whether the mutation(s)
is(are) associated with males or
females.
Give the mutation(s) a madeup name and symbol.
P generation Flies
Make a Table
Make a table with the correct
number of rows label it F1
generation data.
Phenotype
and symbol
Females Males
F1 generation
The following page shows
the results of the parental
cross. Count the flies and
record the results in your
table.
F1 Flies
F2 Flies
Count the flies on the
following page. Make
a table labeled F2
generation data and
record the results.
F2 Flies
Write your lab report