Drosophila Melanogaster : A Model Organism Within Genetics Research Essay

Mendel studied pea plants and how they passed along their genes. Plants that bore green peas that bred with other plants that had green peas had green offspring. Mendel would occasionally breed the green pea plants with plants that had yellow pea plants. The pea plants would only inherit one gene from one parent. If a plant produced more offspring, the chance for a green pea plant increased but most of the offspring would be yellow. This means that even though the dominant trait is more noticeable, the recessive trait was still contained inside the offspring. Evolution can occur based on the distribution of genes in a species population. "From what we know of the genetic nature of inheritance, it is also clear that evolutionary processes must entail changes in the genetic composition of populations" (Boyd and Silk

In this experiment we tested to see what the offspring of an unknown cross of an F1 generation would produce. After observing the F2 generation and recording the data we found some of the Drosophila showed mutations, two in particular. The mutations were the apterus wings, and sepia eyes. After collecting our data through observation, a Chi-test was conducted resulting in a Chi-value of 5.1 and a p-value of .2. Since the p-value was greater than 0.05, there was no significant change in the data. This proved that the Drosophila flies still followed the Mendelian genetics of a 9:3:3:1 ratio.

The foundation of genetics lies with the principles that Gregor Mendel outlined after his experiments with pea plants where he discovered the relationship between physical characteristics, or phenotype, and genetic traits, or genotype. This experiment aimed to reproduce Mendel’s results with the Brassica rapa plant, noted for it’s fast generation time, and anthocyanin, a purple pigment that can be visually tracked through subsequent generations. It is important for experiments resulting in scientific discovery to be replicable and peer reviewed. Since Mendelian genetics are the foundation of scientific education, including answering questions about

Introduction: The intention of this lab was to gain a better understanding of Mendelian genetics and inheritance patterns of the drosophila fruit fly. This was tasked through inspecting phenotypes present in the dihybrid crosses performed on the flies. An experimental virtual fly lab assignment was also used to analyze the inheritance patterns. Specifically, the purpose of our drosophila crosses is to establish which phenotypes are dominant/recessive, if the traits are inherited through autosome or sex chromosomes and whether independent assortment or linkage is responsible for the expressed traits.

He chose to study in detail the common garden pea, Pisum, which he grew in the monastery garden. During 1856 and 1863 Mendel tested his pea plants reaching a number of maybe 28,000 pea plants, carefully examining seven pairs of seeds for comparison, such as shape of seed, color of seed, tall stemmed and short stemmed and tall plants and short plants looking and the differences in the same plant. Johann Mendel worked on this for many years, carefully wrapping each individual plant to prevent accidental pollination by insects. He collected the seeds produced by the plants and studied these seeds observing that some plants. Johann Mendel discovered that by putting together tall and short parent plants he got hybrid result that resembled the tall parent rather than being a medium height blend. He explained his concept of heredity units, now called genes. These often referred to as dominant or recessive characteristics. He then figured out the pattern of inheritance of various and came up two generalizations that became known as the laws of heredity. Johann Mendel's observations led him to coin two terms, which are still used in present-day genetics: dominant and

It would be expected that the mutant F1 flies would be heterozygous for the allele responsible for the grounded trait. If two F1 flies were mated, the percentage of flies that would be expected to be wildtype in the F2 generation would be 25% mutants given that the mutant allele (ap) is predicted to be recessive and, leaving 75% to be wildtype (ap+).

This discovery was made when Morgan was working at Columbia and one day, while observing a male fruit fly, he noticed that instead having bright red eyes as any normal Drosophila melanogaster would, this particular insect had white eyes. Morgan questioned the cause of the color of that fly to be different and wondered how this trait was acquired. In order to answer his questions, Morgan proceeded to do simple breeding analyses with the white-eye fruit fly. This experiment began with a test cross between the white-eyed fly with normal red-eyed females. The results in the first generation was all red eyes. This was shown through the use of Punnett squares. However Morgan didn’t stop there, he took the male and females from the first generation and test crossed them again. This time, the second generation resulted with some flies with the white-eyed trait along with some red-eyed trait. Morgan noticed that the only white-eyed trait however occurred only in the male fruit flies. This led to his hypothesis of sex-limited, also known as sex-linked. However, upon further experimentations, the next generations of crossing the original male with some first generation red-eyed females resulted with both red-eyed and white-eyed males and females, therefore the trait was concluded to be sex-related and the trait of the coloured-eyed gene was found to be on the X-chromosome. Thus the discovery of how genes are transmitted through chromosomes. In 1933, Thomas Morgan

Do genes A and C follow Mendel’s principles of inheritance? Why or why not? Explain fully.

Introduction For centuries, researchers have used Drosophila melanogaster, the common fruit fly, to study genetics. The benefits of using the fruit fly includes: its relatively short generation time, its large amount of available offspring for data, it is easy to store and handle in the laboratory and it is easily and cheaply obtained. Cross-breeding of four types of fruit flies were used in this experiment including: wild type males with normal wings vs. vestigial wing females, wild type males with red eyes vs. white eyed females, wild type male with red eyes vs. sepia eyed females, and wild type males vs. wild type females. In basic mendelian genetics, the terms dominant, recessive and sex-linked are used to describe the different types

30. What attributes of the garden pea plant made it an excellent organism for Gregor Mendel’s genetic studies?

Gregor Johann Mendel, the father of genetics, was born in 1822. He was a priest and scientist who became famous for his work and studies on the inheritance patterns using pea plants. Gregor Mendel used pea plants known as Pisumsativum in his research where he developed two fundamental laws of genetics known today as the “Law of segregation”, and the “Law of independent assortment” (Hartl, 1992). The “Law of segregation” states that when an individual produces a gamete, the copies of a given gene separate in which each gamete receives only one copy of that gene. The phenotypic ratio in the F2 generation according to the “Law of

The Drosophila melanogaster is a fruit fly with a very short life cycle. They can be winged or wingless, and have red eyes or white eyes. The different options are called alleles. Alleles are the variants of a specific gene, and one is received from each parent on each chromosome. (“What Are Dominant and Recessive?”). It was chosen to use winged females and wingless males to predict the offspring in this experiment. The winged allele is dominant, meaning it only needs one allele to physically appear. The wingless allele is recessive, which gets covered up by the dominant allele (“Fruit Fly Genetics”). Each trait has two alleles in the flies’

Genetics shows us that we inherit traits in many different ways. A perfect example to show us the different ways we inherit traits is fruit flies. Fruit flies are commonly used by scientists to conduct genetic experiments due to their reaction to the experiment being very quick. Scientists mainly look at how the flies inherit basic traits such as brown body color, or red eyes(basic trait flies are known as wild-type flies) from their parents, but sometimes they can come across some abnormal traits. Some of these abnormal traits include having a yellow body color or having curly shaped wings and have made scientists wonder how the flies have inherited these specific traits. So how do the flies inherit

“The cellular machinery that copies DNA sometimes makes mistakes,” there are about 37.5 trillion cells in the human body, and their job is to make copies of DNA, yet sometimes the cells make a mistake and either switch, remove, or add a gene. This does not occur often, so when it does these mistakes are called mutations. Another reason that signifies why mutations are unusual is because mutations are mostly recessive traits. In an online article, Fruit Fly Phenotypes it informs us about fruit flies and some of the mutations, “This mutation is a recessive trait, meaning that the fly won't express the gene unless it gets it from both parents.” In other words some mutations are recessive traits meaning both parents must have the trait for the offspring to have the mutation as well. According to a lab, Genetic Variation in Monsters, “Recessive traits only show up if dominant traits are absent and are represented by a lowercase letter. Dominant traits show up in the offspring whenever present.” This is an explanation of what recessive and dominant traits are, in quotes it says that dominant trait are found anywhere where at least

He reasoned that there were certain rules by which these characteristics were inherited. He guessed that each plant must possess some sort of unit that specified its characteristics. In fact, each must have two units, one from each parent plant. If the plant inherited two different units, then one would override the other. This was called the dominant unit, and the one that was overridden was called the recessive unit. Mendel's theories were not discovered till 1900, and it began the science called genetics , the study of a physical inheritance. From this name, Mendel's units were changed into genes.