Genetics((Drosophila)) - Lab Report Example

Genetics (Drosophila) Task: According to Mendel’s Law, every organism has two factors. Every gamete has one factor. During segregation, the factors join up in twos to allow for variability of the new daughter cells. Mendel’s Law describes that an organism with genes, A and B, has factors, A, a, B, and b. there are only four possible combinations that can arise as a result of the gametes. These include AB, Ab, aB, and ab. The variety in combination is useful in producing genetic variability in offspring.

Otherwise, for the combination to be perfectly independent, the genes are assumed to be on different chromosomes. IntroductionDrosophila which is the common fruit fly has been used extensively in carrying out genetic research. This is due to the fact that the species is relatively stable. There are many factors that make Drosophila suitable for carrying out genetic research. They have mutations that can easily be differentiated from one another. They are able to produce large number of offspring which can be easily calculated into ratios.

Furthermore, they are small and have four pairs of chromosomes which make it easy to discern them. They are convenient to work with as far as study period is concerned by the fact that they have a life cycle of 12 days. In this practical Drosophila is used to study Mendel’s Law in organisms. GenotypesPhenotypesPVgvg * wtwtVestigial wing * wild typeF1Vgwt * vgwtNormal wing and Normal typeF2VgVg * Vgwt * Vgwt * wtwtVestigial wings * Normal wing and Normal type * wild typeF2:MalesFemalesVestigial wings 1/41/4Wild type 1/41/4(normal wings)1/21/2Total11GenotypesPhenotypesPXY * xxWhite males * type femalesF1xY * XxNormal males and white femalesF2xX * xx * YX * YxWhite females * wild type females * white males * wild maleF2:MalesFemalesWhite-eyed 1/31/3Wild type1/31/3(red eyes)1/31/3Total11GenotypesPhenotypesPXY/wtwt * xx/vgvgWhite males * vestigial femalesF1Xx/wtwt * Xx/vgvg * xY/vgvg * xY/wtwtVestigial and white females* vestigial and white malesF2XY/wtvg * xx/wtvg *Xx/wtwtWhite vestigial male * white vestigial femaleF2 Phenotype MalesFemalesWild type’ (normal wings, red eyes)1/41/4White-eyed, (normal wings, white eyes) 3/85/8Vestigial-winged, (vestigial wings, red eyes)1/41/4White-eye – vestigial-winged, (vestigial wings, white eyes)2/34/7MALE ONLYObserved ratioExpected numbersExpected ratio(O-E)2/EWild type( wings & eye normal)1/42/33/84/5White-eyed( Normal wing)3/42/31/23/7Vestigial-winged( Normal eyes)4/53/41/21/2White-eyed and Vestigial-winged1/23/41/21/2FEMALE ONLYObserved ratioExpected numbersExpected ratio(O-E)2/EWild type( wings & eye normal)3/52/51/27/9White-eyed( Normal wing)2/52/33/45/7Vestigial-winged( Normal eyes)4/71/23/42/3White-eyed and Vestigial-winged2/31/22/34/5The degrees of freedom is one DiscussionI would accept the hypothesis as the results are logical with it.

The results, of course, make sense as they are consistent with theories of Mendel’s Law. They have occurred as expected. The subsequent generations inherit the traits of their parents. The inheritance takes place according to the predictions of Mendel’s law. Combination of alleles is useful in producing variability of offspring. It is assumed that the alleles occur in spate chromosomes. Otherwise, the combination would not be effective if the factors come from the same chromosome.ReferencesOrel, V. (1996). Gregor Mendel: The first geneticist.

New York: Oxford University Press. Russell, P. J. (1998). Genetics. Menlo Park, Calif: Benjamin/Cummings. Stansfield, D., & Hademenos, J. (2003). Genetics. New York: McGraw-Hill. Bottom of Form