Drosophila Melanogaster Lab Report
The Frequency of Mutations among Second Generation Drosophila melanogaster
INTRODUCTION
This experiment involved observing and comparing the relative frequencies of inherited dominant and recessive genes in a population using the common fruit fly Drosophila melanogaster. In this experiment, we demonstrate how dominant genes are selected over recessive genes (Mendel’s Law of Independent Assortment).
Hypothesis: If we cross two heterozygous individuals, our observed offspring in the second generation (F2) will have a phenotypic ratio equivalent to the expected Mendelian probability of 9:3:3:1.
MATERIALS AND METHODS
For this experiment we would observe the offspring that would be produced if we cross breed two heterozygous individuals, this is the first generation (F1). The parents of the F1 generation were a di-hybrid cross of ebony body and vestigial winged Drosophila, which are both recessive also known as mutants. Using statists as a tool we could predict the expected offspring for our F2 generation. The expected is our …show more content…
We applied water to the medium, the white flakes turn blue when mixed with water; the purpose of the blue dye is to make observing the eggs and larvae easier. Next we folded plastic mesh to create a fruit fly “jungle gym.” The jungle gym acts as a breeding ground and resting place for the adult flies. We then anesthetized our fruit flies using FlyNap; FlyNap was used to prevent flies from escaping during observation. A minimum of four females and three males were selected from the F1 generation. Using a camel’s- hairbrush, we examined the fruit flies using a dissecting microscope with a magnification between 12X and 15X. The sexed flies were then placed into Drosophila vials and into the fruit fly home for one
INTRODUCTION
This experiment involved observing and comparing the relative frequencies of inherited dominant and recessive genes in a population using the common fruit fly Drosophila melanogaster. In this experiment, we demonstrate how dominant genes are selected over recessive genes (Mendel’s Law of Independent Assortment).
Hypothesis: If we cross two heterozygous individuals, our observed offspring in the second generation (F2) will have a phenotypic ratio equivalent to the expected Mendelian probability of 9:3:3:1.
MATERIALS AND METHODS
For this experiment we would observe the offspring that would be produced if we cross breed two heterozygous individuals, this is the first generation (F1). The parents of the F1 generation were a di-hybrid cross of ebony body and vestigial winged Drosophila, which are both recessive also known as mutants. Using statists as a tool we could predict the expected offspring for our F2 generation. The expected is our …show more content…
We applied water to the medium, the white flakes turn blue when mixed with water; the purpose of the blue dye is to make observing the eggs and larvae easier. Next we folded plastic mesh to create a fruit fly “jungle gym.” The jungle gym acts as a breeding ground and resting place for the adult flies. We then anesthetized our fruit flies using FlyNap; FlyNap was used to prevent flies from escaping during observation. A minimum of four females and three males were selected from the F1 generation. Using a camel’s- hairbrush, we examined the fruit flies using a dissecting microscope with a magnification between 12X and 15X. The sexed flies were then placed into Drosophila vials and into the fruit fly home for one