The purpose of this experiment is to conduct genetics studies using drosophila fly as the test organism. Scientists can study the basic biology that is shared by all organisms using a model organism, such as drosophila fly1. Drosophila fly, or more commonly known as fruit fly, has several qualities that makes it well suited for experimental genetics cross. First, fruit flies are low maintenance organisms. They are small in size (few millimeters long), so they occupy a small space and a lot of them can fit in one vial at the same time. They only require a media to feed on. In this lab, instant media was used, which is efficient as it only requires the addition of water to be used. This media contains ingredients that the fruit fly can feed one, …show more content…
Three pairs are autosomal, while the last pair of chromosomes are the sex chromosomes. Similar to humans, a XX pair of sex chromosomes will be a female, while an XY sex chromosomes will be a male. However, the determination of sex in fruit flies is somewhat different than in humans. The sex is determined by the X-chromosome’s ratio (X) to the autosomal chromosomes (A). For instance, when the X to A ratio is one or more, the offspring is a female, but when that ratio is less than one, the offspring is a male. Moreover, drosophila fly goes through three life stages until it becomes an adult fly. Approximately one day after the adult female lays the eggs, these eggs hatch into a larvae (Figure 1). During the larval stage, the larva stays in the nutrient media in order to eat and grow. The next stage is the pupal stage where the pupa forms a case around itself that helps metamorphism to occur. The pupa becomes darker in color and stiffer. Finally, when metamorphism is complete, the adult fly comes out being fully developed and having wings, legs, and eyes. An adult fruit fly may live approximately 30 …show more content…
One key distinction is the sex combs on the male’s foreleg, which is characteristic that is lacking in the females. Another way to distinguish the sex of the flies is to carefully examine the tip of the abdomen in each. The females tend to have a lighter colored abdomen that is more pointy and long. On the other hand, males tend to have darker pigmented abdomen that is round and short. In general, females tend to have a larger body than males. Sex determination can easily be accomplished even under a low power magnification, which adds to the ease of using fruit flies to study genetic
Variation in selection pressures on the goldenrod gall fly and the competitive interactions of its natural enemies
In order to figure out the genes responsible, there are several other factors that must be determined. These factors include the number of genes involved, if each gene is x-linked or autosomal, if the mutant or wild-type allele for each is dominant, and if genes are linked or on different chromosomes. Proposed crosses include reciprocal crosses between the pure-breeding mutants of strains A and B with the wild-type will help determine if the genes or sex-linked or autosomal, in addition to which alleles are dominant (8). Another proposed cross includes complementation crosses between pure-breading mutants from strains A and B to determine if one or two genes are involved (8). Furthermore, testcrosses between F1 progeny and pure-breeding recessive mutants from strains A and B, which will help determine if genes are linked on the chromosome or if they assort independently (8). These proposed crosses are shown in the attached
17. Fruit flies normally have eight chromosomes. The diagram below shows the result of meiosis in three fruit flies to produce gametes with the number of chromosomes indicated. The male then mates with both female A and female B to produce three zygotes (1, 2, and 3).
Conclusion for class di-hybrid cross: The p value 0.779 is in the non-significant range in the chi square table. The null hypothesis is therefore correct. Sepia eyes and vestigial wings in the flies is a mutation in the genes that is not linked meaning it is a product of independent assortment.
In science, these fruit flies can be used to study genes and mutations relatively quickly because of the limited life span. Knowing mating behaviors can help scientists better understand their results and improve their experiment designs to reduce
They are very popular because they have a relatively short life cycle, which lasts about 9 days. This makes it easy to observe multiple generations in a short period of time. The fly’s life cycle consists of egg, larvae, pupa, and adult stages. At each of these stages of development, Drosophila exhibits different phonotypical identities and mutations. The flies that were crossed contained a genetic mutation called apterous. Apterous can be observed by looking for flied that are missing wings. Flies with apterous will not have any wings. If this mutation is sex linked, it is expected that the male population will only be wingless in the F2 generation. If the mutational is autosomal, it is expected that the mutation to normal fly ratio is
An individual can be homozygous dominant (two dominant alleles, AA), homozygous recessive (two recessive alleles, aa), or heterozygous (one dominant and one recessive allele, Aa). There were two particular crosses that took place in this experiment. The first cross-performed was Ebony Bodies versus Vestigle Wings, where Long wings are dominant over short wings and normal bodies are dominant over black bodies. The other cross that was performed was White versus Wild where red eyes in fruit flies are dominant over white eyes. The purpose of the first experiment, Ebony vs. Vestigle was to see how many of the offspring had normal bodies and normal wings, normal bodies and vestigle wings, ebony bodies and normal wings, and ebony body and vestigle wings.
Multiple allele is when more that one allele is being crossed and all of the traits are being crossed together. Sex linked inheritance is when the gene for a certain trait is carried on either the X or Y chromosomes for the parent. The goal of this lab is to better understand genetics. The guiding question is, Which model of inheritance best explains how a specific trait is inherited in fruit flies? In first population, the model of inheritance was dominant-recessive and the wild body type is dominant and the aristapedia body type is recessive.In the second population, the model of inheritance is incomplete dominance because the mellow trait crossed with the hyper trait combines to make the spontaneous trait. In the third population, the model of inheritance was sex linked recessive to the yellow colored trait on the X chromosome. In the fourth population, the model of inheritance was a multiple allele autosomal cross for the different traits.
Richard Wilbur's recent poem 'Mayflies' reminds us that the American Romantic tradition that Robert Frost most famously brought into the 20th century has made it safely into the 21st. Like many of Frost's short lyric poems, 'Mayflies' describes one person's encounter with an ordinary but easily overlooked piece of nature'in this case, a cloud of mayflies spotted in a 'sombre forest'(l.1) rising over 'unseen pools'(l.2),'made surprisingly attractive and meaningful by the speaker's special scrutiny of it. The ultimate attraction of Wilbur's mayflies would appear to be the meaning he finds in them. This seems to be an unremittingly positive poem, even as it glimpses the dark subjects of human isolation and mortality, perhaps especially as it glimpses these subjects. In this way the poem may recall that most persistent criticism of Wilbur's work, that it is too optimistic, too safe. The poet-critic Randall Jarrell, though an early admirer of Wilbur, once wrote that 'he obsessively sees, and shows, the bright underside of every dark thing'?something Frost was never accused of (Jarrell 332). Yet, when we examine the poem closely, and in particular the series of comparisons by which Wilbur elevates his mayflies into the realm of beauty and truth, the poem concedes something less ?bright? or felicitous about what it finally calls its 'joyful . . . task' of poetic perception and representation (l.23).
The class insect has the same body structures and functions. They have a segmented body divided into three parts, head, abdomen and thorax. They also have an antenna, segmented legs, and wings. The functions of the body parts, however differ from the different orders of insects. For instance the mouth parts for an adult ladybird beetle is chewing, but on a Hemiptera the mouth form is a beak called the stylets as is the case with an aphid. Palps are on the ends of beetle’s mouth and are used for picking up and holding food while eating. The only visible top part of the thorax on a ladybird beetle is the pronotum, while on other insect such as Hemipteras the pronotum is a triangular shape and is then called the scutellum. Typical beetles have two sets of wings, the front set called elytra, which
I absolutely loved Stick Fly—my attention was captured during the entire play. There were moments when and I cried and there were other moments when I laughed. The scene was amazing! It looked so realistic, especially the bookshelf and the kitchen cabinets. I could have lived in that house if it was really a house. The set design and the actors’ clothes fit in with the time period. The lighting was great also. There were these window panels hanging around the room and as the scenes changed the lights over the panels caught people’s attention. I would notice people turning around looking at the lights. Also my favorite was the light outside of the kitchen window. Once again, it looked very realistic the light would change as the time of day changed. You were able to notice when it was day, evening, and night due to the light from the kitchen window. Another thing that made the scene so realistic was that the sink actually worked. Overall, the set was amazing!
The fruit fly is a model system that is used to study genetics due its short life cycle, large number of offspring, easy culturing conditions and low cost. It produces a large sample size from which predictions can be determined about inheritance patterns. It has a simple chromosome organization, 3 pair of autosomal chromosomes and 1 pair of sex chromosome. The four stages of the fruit fly life cycle are egg, larva, pupa and adult. The generation time of Drosophila melanogaster is 2 weeks: 8 days in the egg and larval stages, and 6 days in the pupal stage. The adult may live up to 8 weeks under optimal
There are nearly one million species of insects known. Insects are defined by having six legs and a body divided into three segments: head, thorax, and abdomen. Chitin is an organic material that makes up an insects exoskeleton. There are three life cycles of insects, ametabolous or incomplete and paurometabolous or gradual, and homotabolous or complete metamorphosis. These life cycles are important in the aging of insects for aiding in legal investigations, (Houck and Siegel. Entomology).
Insect, small, air-breathing animal characterized by a segmented body with three main parts—head, thorax, and abdomen. In their adult forms, insects typically have three pairs of legs, one pair of antennae, and in most instances, two pairs of wings. Insects rank among the most successful animals on Earth. About one million species of insects have been identified so far, which is about half of all the animals known to science. That is why for every pound of human on the earth there are 10 pounds of insects. So that is why there are many reasons why insects are so successful, their exoskeleton, their size, their body function, the way they reproduce, and their development of metamorphosis.
Sex and gender are terms that are mixed up from day to day and seen as similarities rather than differences. Sex is what distinguishes people from being either male or female. It is the natural or biological variation between males and females (Browne, 1998). Some of these variations are genital, body hair, and internal and external organs. It is the make-up of chromosomes, men have one X and one Y chromosome and women have two X chromosomes, which are responsible for primary characteristics (Fulcher and Scott, 2003).