Drosophilia Fly Project:
Objective: To learn and apply the principles of Mendelian inheritance by experimentation
with the fruit fly Drosophila melanogaster. Groups will formulate hypotheses for
monohybrid traits and test their hypotheses by selecting fruit flies with different visible
mutations, mating them, and analyzing the phenotypic ratios of the offspring. Groups will
record their observations into an online notebook and write an online lab report.
Expected learning outcomes:

Demonstrate the meaning of dominant and recessive traits.

Make predictions about a scientific outcome and test for accuracy.

Formulate and revise scientific explanations and models using logic and evidence.

Recognize and analyze alternative explanations and models.

Communicate and defend a scientific argument.
Question to answer: Which model of inheritance best explains how a specific trait is
inherited in fruit flies?
Traits to choose from (each group is only required to choose one): Black body (b), curved
wings (c), ebony body (e), or lobe eyes (l).
Day 1:

Preview the activity and expected outcomes. Read Lab 21.

Register a group account.

Become familiar with the online activity.

Decide on one trait to test and formulate a hypothesis of mating outcomes.

If time…order your first flies and do the F1 cross. Remember to send all your data
to the online notebook.
Day 2:

Order flies for trait to test (if didn’t order on day 1)

Do the F1 cross and F2 cross for that trait.

Determine if hypothesis is correct and make adjustments to model if necessary.

Many crosses should be done!

Start designing poster for arguments.
Day 3:

Make arguments for hypothesis/model based on poster work.

Type up report for group using online report tab in simulation.

Complete the online quiz as a group. This must be done before leaving on Day 3.
Project due date: June 11th at 11:59 PM. (for online report)
Grading: Total for project: 110 points for exam grade.

Poster-18 points (see rubric below).

Online Report-92 points (see rubric online).

Quiz-10 points (based on percentage online)—extra credit.
Poster rubric:
High Proficiency (6 pts
each row)
Content and
Analysis
-Contains a clear,
compelling claim.
-Claim demonstrates
insightful
comprehension.
Command of
Evidence
-Central claim is wellsupported by scientific
evidence.
Coherence and
Organization
-The presentation is
clear and follows
example.
-The logic can be
followed in a clear
pattern of purpose.
Approaching
Proficiency (5 pts
each row)
-Contains a clear
claim.
-Claim demonstrates
sufficient
comprehension and
basic inferences.
-Central claim is
somewhat supported
by scientific
evidence.
-The presentation
isn’t very clear, but
follows example.
-There is an attempt
to follow a logical
pattern.
Not Proficient (4
pts each row)
-Contains a clear
claim.
-Claim doesn’t
demonstrate
comprehension of
basic objectives.
-Central claim isn’t
supported by
scientific evidence.
-The presentation
isn’t very clear and
doesn’t follow the
example or a logical
pattern.
Notes to get started:
What is the difference between validity and reliability?
Validity-- refers to how well a test measures what it is professed to measure.
Reliability-- the degree to which an assessment tool produces stable and consistent
results.
Hints for the program:

Wild type allele will show as a + in flies (all orders from the store start out
homozygous)--That is the same as a big letter if the mutant is recessive. It would
be the small letter if the mutant is dominant.

Mutant (all orders from the store start out homozygous) is the small letter if the
mutant is recessive. It would be the big letter if the mutant is dominant.

Test cross: wild type fly crossed with a homozygous recessive mutant.

When doing your tests, make sure you do the following:
o
Students should try reciprocal crosses (female mutant vs. male wild type and
female wild type vs. male mutant).
o
Students should try a test cross for recessive traits. Mate a F1 wild type to
a homozygous recessive mutant from the store.
o
Students should cross an F1 x F1 to get an F2 generation. Think about your
expected outcomes by doing a practice Punnett square.

Chi-Square analysis is optional, but suggested for strengthening your argument.