Name: ______________________________________
Period: ______
Drosophila Activity D
AP Biology
Activity B Recap: Scoring F1 Phenotypes and Setting up F1 Crosses (to be discussed in lab)
 Fly Phenotype Symbols
Symbol
Name (same as phenotype)

F1 Cross
Parental Cross
Phenotypes Observed in F1
Inheritance Pattern
Activity C Recap: Removing F1 Adults from Vials
 F1 flies were removed from vials that had fly eggs and larvae. Why is it necessary to remove the F1
flies?

The F2 generation consisted of eggs and/or larvae in the vial. Channels in the culture medium were
visible. The black mouthparts of the larvae moving under the surface of the medium were also visible.
Activity D: Scoring Phenotypes of F2 Flies
Materials
 Sorting brushes
 Sorting cards
 Fly morgue



Microscope
F1 cross vial
Fly Nap® Kit
Procedure
1. After the F2 adults begin to emerge, score them as to sex and the presence or absence of the phenotypes
observed in the parental flies. To do this, transfer the adults to an empty culture vial and anesthesize
them using Fly Nap®. Make sure to where gloves while handling Fly Nap®. Do not directly inhale the
vapors. Close the Fly Nap® bottle as soon as possible to avoid excess vapors.
2. When the flies are asleep, sprinkle them onto a card or into a petri dish and score them.
3. Record the results in a data table. The more F2 flies collected, the more reliable the data will be.
4. When you have finished scoring the flies, put them in the morgue.
Clean-up
1. All Parental, F1, and F2 flies must be disposed of.
a. Transfer the adults to an empty culture vial and anesthesize them using Fly Nap®. Make sure to
where gloves while handling Fly Nap®. Do not directly inhale the vapors. Close the Fly Nap®
bottle as soon as possible to avoid excess vapors.
b. Once the flies are asleep, transfer them to the morgue.
2. All petri dishes, sorting cards, and empty F1 cross vials may be thrown in the trash.
3. Wash your hands before you leave lab (especially after handling Fly Nap®).
Analysis
1. According to the F1 generation and the pattern of inheritance, what is the expected phenotypic ratio in
the F2 offspring? Include a number ratio and a phenotype description ratio (1:2:3 and green eyes: purple
eyes: pink eyes).
2. What is the observed phenotypic ratio in the F2 offspring? Include a number ratio and a phenotype
description ratio (1:2:3 and green eyes: purple eyes: pink eyes).
3. Perform a chi-square statistical analysis to determine if there is a significant difference between the
observed phenotypic ratio and the expected phenotypic ratio.
a. Calculate the chi-square value.
b. Determine the degrees of freedom.
c. Determine the p value.
d. Is there a significant difference between the observed phenotypic ratio and the expected phenotypic
ratio?
Due Date: Tuesday February 16, 2016 (in class)
RUBRIC MUST BE STAPLED TO THE FRONT OF YOUR LAB. IF NOT… 10 POINT DEDUCTION.
Name: ______________________________________
Period: ______
Genetics of Drosophila
Week 3 Lab Report Rubric
AP Biology
Introduction
What knowledge already exists about this
subject?
a. What is the F1 cross being studied?
b. What is the type of inheritance?
What is the specific purpose of the study?
What were you trying to accomplish the
third week in lab?
Miscellaneous: spelling, grammar,
sentence structure, etc.
Maximum Points
Data Table
Created using a ruler.
Maximum Points
All columns and rows labeled
correctly/clearly.
Identifies all possible phenotypes observed
in the F2 offspring (if sex-linked, record
male and female as phenotypes).
Contains the number of F2 offspring that
have each phenotype.
Analysis
According to the F1 generation and the
pattern of inheritance, what is the expected
phenotypic ratio in the F2 offspring?
 Number ratio
 Phenotype description ratio
What is the observed phenotypic ratio in
the F2 offspring?
 Number ratio
 Phenotype description ratio
Chi Square Analysis
 Calculate the chi-square value.
 Determine the degrees of freedom.
 Determine the p value (can be an
inequality).
 Is there a significant difference
between the observed phenotypic
ratio and the expected phenotypic
ratio?
 Shows work!!!
Points Earned
10 points
10 points
5 points
Points Earned
5 points
5 points
10 points
10 points
Maximum Points
Points Earned
10 points
10 points
5 points
5 points
5 points
5 points
5 points
RUBRIC MUST BE STAPLED TO YOUR LAB (or a 10 POINT DEDUCTION) Total: ______________