Investigation

Fruit Fly Project

fiveblue1, fiveblue2, and fiveblue3

Introduction

The reason for our project was to try and figure out how the white eye mutation is passed down in flies. The other phenotype of fly (other than white eyed) was the wild fruit fly(red eyed). The reason we used fruit flies was because they breed fast and they are seen as pests to our human supremacy. Overall we are hoping to find out how white eyes are passed from one generation to another.

Characteristics 

Kingdom-Animalia

Phylum-Arthropoda

appendages, compound eyes, segmented antennae,open circulatory systems, exoskeleton

Class-Insecta

segmented body, usually small, wings

Order-Diptera

one pair of wings, may sting, make honey

Family-Drosophilidae

Genus-Drosophila

Species-melanogaster

Phenotypes

There are two main phenotypes (phenotype is just a big word for the type of fly) that were involved in our experiments were wild (red eyed) and white (white eyed). So the description for each is very similar in almost all aspects of physical characteristics except for the color eyes. As you can assume the white have white eyes and the wild have red eyes.

OBSERVATION LOG

Date    Observation

2-27        Flies expand to new cultures
3-2          No sign of larva medium dry-added water
3-3          Larva is alive and is eating and borrowing
3-6          Pupas forming, larva moving
3-7          Pupas turn into flies, cocoons higher up
3-8          More pupa & cocoons still a good number of flies
3-10        we see all stages
3-13        35 of larva ready to hatch, still flies
3-16        p1 cross vial1 5 female 6 male vial2 6 male 6 female no larva
3-17        cocoons, all flies alive vial1 napped vial2 a few deaths most part good
3-20        larva some flies die in both vials
3-21        more larva, moved higher more dead flies
3-22        more larva mostly red some white
3-23        more dead flies only a few still alive vial 2 more larva higher up.
4-3          vial2 four flies died vial1 one fly dies
4-8          saw pupa saw larva killed removed f1 adults
4-17        vial1 many red eyes vial2 lots of flies majority red
4-24        vial1 new flies some larva vial2 many new flies

Sexing

 F1 predictions

  +
+
W W+ W+
W W+ W+

(key: += wild W=White)
If white eyes are dominant, then all F1 offspring will be heterozygous white eye.

  +
+
w +w +w
w +w +w

If wild is dominant then the offspring will be all wild eyed and heterozygous.

F1 outcomes

vial 1 P cross= female white X male wild

f1 female Phenotype=white 

likely genotypes for f1 Males= XwY

 
Vial 1 P Cross=female wild X white male

f1 Male Phenotype=wild eye (all)

likely genotypes for f1 females=X+Xw hetro

 
Vial 2 P cross=female wild X white male

f1 male Phenotype=wild eye (all)

likely genotypes for f1 males=X+Y

 

Vial 2 P Cross=wild female X white male

f1 female Phenotype= all wild

likely genotypes for f1 females=X+Xw hetro

F2 Predictions

These tables show the expected outcomes for the second generation of flies.  

Vial 1 

   Xw  Y
 X+  X+Xw X+Y 
 Xw  XwXw  XwY

 50% wild (25% male,25% female)

 50% white(25% male, 25% female) 

Vial 2 

   X+ Y
 Xw XwX+
XwY
X+ Xw+
X+Y

 25% Male white

 50% Wild female

 25% Wild Male 

Fly Count

 Vial 1

The lack of flies is because of a problem during transferring when the medium covered all of the larva and killing of most of the generation. 

 Date Female Wild
Male Wild
Female White
Male White
 2-21-06 22
22
15
11
2-24-06
2
0
0
0
2-25-06
3
7
2
1
Total= 85
27
 29 17
12

 Vial 2

Date  Female Wild
Male Wild
Female White
Male White
4-21-06
17
6
0
12
4-24-06
10
2
0
3
4-25-06
2
1
0
0
Total=53
29
9
0
15

Percent Error Analysis 

vial 1!

 phenotype  observed expected   (O-E)  (O-E)/E  X 100
%error
 Wild Male
 29  21  8  .38  38  38%
 Wild Female
 27  21 6  .28  28  28%
 White Male
 12 21   9  .42  42  42%
 White Female
 17  21  5  .23   23  23%

Vial 2

 phenotype  observed  expected  (o-e)  (O-E)/E  X100  %Error
Wild male   9  13  4  .30  30  30%
 Wild female
 29 26  3  .06  6  6%
 White male
 15  13  .15  15  15%
             

Conclusion

Overall, I think that we learned how to work together to complete our fly assignment. We all put in time and work. The only thing that we would want to do differently would be to start working sooner rather than later.  We would also take better notes and pay more attention to produce better results. Even though we never would have thought about fruit flies outside of the science room, we did learn a lot about the different types of mutations and the life cycle of the flies. We learned about almost every aspect of the flies life and we also got the chance to participate in the breeding of the flies. Our hypothesis was that white eyes were a sex linked recessive trait. For the most part, our data followed our hypothesis. Our range of error went from a low 6% to a high 42%. Although our percent error was high in some places it was due to transferring mistakes. The only times that we had any difficulty with our flies was, as I mentioned earlier, a transferring mistake. We didn't really have many questions, and the ones we did have were answered.

Eulogy

To all the flies that we brutally massacred in the name of science we're sorry.... kinda. 

About This Page

Author: fiveblue1, fiveblue2, and fiveblue3
Classroom Project: fiveblue
city high school
Tucson, AZ USA

License: Tree of Life & Partners uses only - Version 1.0

Correspondence regarding this page should be directed to , city high school

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