Meiosis and Genetic Diversity in the Model Organism

4 November 2013 Section 24 TA- Erik Ohlson Meiosis and Genetic Diversity in the Model Organism, Sordaria flmicola Introduction Research groups from the Imperial College of Science, Technology and Medicine and the bring in of Evolution at the University of Haifa have been studying the ins false topazce organism, Sordaria fimicola, in regards to unequivocal cross everyplace frequency in response to environmental pressures. Sordaria fimicola is a good model organism because it has a fast life turn and elongated asci that atomic number 18 easily seen under a microscope.In addition, in that location are multiple unlike combinations of ascospore olors collect to recombination during meiosis. Evolution Canyon is the research model for this audition because of its exceedingly differing careens. The South facing slope (SFS) receives high temperatures and droughts due to the high solar radiation. On the other hand, the North facing slope (NFS) exhibits shadier, cooler, and more humid climates. Asexual filaments were collected from either slope and heavy(p) in the lab.Wild fictitious character spores( stern spores) were acquired from self-cross between the asexual filaments and spore color mutants (tan spores) were obtained from brainsick cause trains that produced non-black spores that arose spontaneously within all(prenominal) population. They made crosses with wild type vs. tan spores from differing slopes (NFS-SFS) and found that cross over frequencies between the differing slopes was great (Hass and Ward, 2010). Contrary to prior belief, cellular mechanisms were influenced by environmental conditions this tells us that differing environments can lead to different recombination frequencies.In our part of the experiment, we created a control where the spores were grown under the same best lab conditions. The combinations of ascospores we observed include, 44, 2222, and 242. During meiosis, 4 ascospores are produced after crossing over occurs. then the spores undergo a series of mitosis where 8 spores are then created. In a 44 recombination, there could either be 4 tan then 4 black or 4 black than 4 tan. In the 2222, there could be tan, black, tan, black or vice versa. In the 242, there could be tan, black, tan and so on.Therefore, 6 different combinations asci classes can occur. Our determination for this experiment was to identify the different spores, cross over frequency, and mapping distance. However, there were challenges in preparing the squashes, and then identifying the different spores. Methods We divided the petri dish into four sections, where the wild black type samples were diagonal from each other and the tan type samples were also diagonal from each other hyphae side down onto wedlock agar to increase the possibility of crossing over to occur.After two weeks, utilise an inoculating loop, we scraped some perithecia from the center of the dividing lines where we believed crossing over occurred. We then put them on slides with a drop of water to observe the crossing over requencies under a microscope. Pressure was applied to the coverslip in order to sap the asci from within the perithecia in order to count the frequency of each asci type. To consider cross over frequency and map distance, we used the formulas 1. % Cross everywhere=( of recombinant asci/ total asci) x 100% 2.Map Distance= % cross over/ 2 *Note that map distance accounts for all spores, but in our experiment only half crossed over, we divide by 2. Results Table 1. person Data. This illustrates the number each recombination found within our picture we were provided. Non-recombinant Recombinant match of Asci Total Recombant Asci (B+C) of Type A Asci of Type B Asci of Type C Asci 8 5 3 4 Table 1 illustrates the number each recombination found within our picture we