The yellow mutation is sex-linked gene which is located on a sex chromosome. Assume you identify flies and record the following data for the offspring of an unknown cross involving a single trait. With this data, a chi-square analysis was conducted.
Anesthetize the flies using ether your instructor will demonstrate. Under normal diploid conditions a female fruit fly has two X chromosomes, a male has an X and a Y chromosome. Metamorphosis takes place during the pupal stage. Drosophila melanogaster have 4 chromosomes, all of which have been mapped out showing us that the ebony mutation is located on chromosome 3.
The reason it is so widely used is because it is easily cultured in the lab, has a short generation time, and can produce many offspring.
This way there are enough fumes in the vial to knock out the fly but there is less risk of killing it. Once the F2 generation starts to emerge they are counted.
After about 20 seconds we removed the stopper and replaced it will a clean one. The males and females were both then closely examined for wild type or ebony phenotype. Drosophila can go from egg to adult in just 12 days with a few other stages in between.
For example, the mutant "ebony" has a much darker body than the wild type fly. You should begin with a wild type fly so that you will have some basis for comparison.
Before you begin the lab today, you should learn a little about the life cycle of fruit flies. After the fly emerges, the wings expand and dry, the abdomen becomes more rotund, and the color of the body darkens.
Mendel cross pollinated pure bred plants and discovered that traits are passed on to offspring in the F2 generation at a 3: Once the fly is isolated we anesthetized it using FlyNap which was supplied by Carolina Biological Supply.
This requires a bit of detective work, since there are several possible parental crosses. The number of wild type and ebony phenotype present within gender groups was then recorded. Once the fly is asleep, we observed it under a dissecting scope or magnifying glass to determine gender.
In the first cross you are given there is a single mutation. Of course, fruit flies also have sex chromosomes and they contain a subset of genes as well.
The idea here is to work back to the parental genotypes from the ratios of the F1 phenotypes you are given today. By day 7, there are large, visible larvae in the medium.
Females are sexually mature after 8 hours and can then begin to mate and lay eggs. The chart below shows the complete linkage and mapping for Drosophila melanogaster.
All flies that emerge once the F1 parents have been removed are now F2 generation. The above description is for a gene located on an autosome a non-sex chromosome. By breeding this mutant with the normal red eye flies Morgan showed that the white eyes were a sex-linked mutation and went on to explain sex-linked inheritance and chromosome theory.
Drosophila is widely used for education because it is a fantastic model organism. Is your mutation on an autosome or sex chromosome? Simple Mendelian Genetics in Drosophila Lab objectives: These larvae will then pupae for about 4 days before emerging adults.
How would you tell? Thus, in the case of ebony, the code is a lower case e. We then took the swab and pressed the non-cotton end into the cotton stopper and closed the vial with the swab inside. These larvae feed voraciously on the culture medium provided.
All flies that emerge after the parents are removed are F1 generation and are placed into a new vial with fresh medium.
Again, after 7 to 10 days once larvae appear the parents are removed. From this he was able to conclude that the inheritance of each trait is determined by units genesthat individuals inherit one unit from each parent for each trait, and that while traits may not show up in the individual they can still be passed to the next generation.
Our group was given the mutant type Ebony which has a black body.Simple Mendelian Genetics in Drosophila. Lab objectives. 1) To familiarize you with an important research organism, the fruit fly, Drosophila melanogaster.
2) Introduce you to normal "wild type" and various mutant phenotypes. Report abuse. Transcript of Drosophila Lab. Genetics of Fruit Flies If the genes follow Mendelian genetics and if the star eyed gene is dominant to the wild type gene, then the cross between the Star-eyed female parent and the Wild-type male parent will produce Star-eyed flies and wild type flies in a ratio (used in the parent.
View Notes - Drosophila Fly Genetics Lab Report from BIOL L at University of South Carolina. Biology Lab 26 November Discovering Mendelian Genetics Using 94%(50). Drosophila Genetics: Applying Mendelian Principles through Experimental and Empirical Methodology Jayanth (Jay) Krishnan this experiment we used Drosophila melanogaster commonly known as fruit flies to computationally, experimentally, and empirically understand some important genetic principles Drosophila Genetics Lab Report.
Drosophila Genetics: Applying Mendelian Principles through Experimental and Empirical Methodology Jayanth (Jay) Krishnan T.A. Ms. Bianca Pier Lab Partner: Ms. Catherine Mahoney Lab Report done with Tanuj Sharma Section 1: Biology October 19th, 1 Purpose: What did we want to do?
LAB 11 – Drosophila Genetics Introduction: Drosophila melanogaster, the fruit fly, is an excellent organism for genetics studies because it The Discussion section of your lab report will include your discussion of the significance of your Chi-Square analysis results.
This is essential! Do not forget to properly explain what your.Download