Discussion Section michelle wk 6 p1

Discussion Section michelle wk 6 p1 - o All the numbers...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
BICD-100 Genetics Ghiara Spring 08 Week 6- Tuesday Chi-Squared Analysis - Why do we need to use a Chi-Squared Analysis? - How to use it: o Collect data and categorize the classes. o Collected data is observed values. o Need to find expected values. How would you do this? o Calculate Chi-squared value. - = Expected Expected Observed 2 2 ) ( χ o Calculate the df (degrees of freedom). 1 - = n df o Use chi-squared and df on chart (Table 3.4 or 3.2 in text book) - Critical Value Chi-Squared value = 5.9991, P = 0.05. This is the “cut-off range” assumed in biological experiments. o If below Critical Value data is accepted, proves hypothesis is correct, and errors are most likely due to chance. o If above Critical Value data is not accepted; hypothesis is wrong, and errors are significant (there is something significant going on with the genes) - How to read the Chi-Squared Table: o Df = degrees of freedom (obviously) o P = probability of that particular chi-squared value of the experiment to occur in that df.
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: o All the numbers checkered all over the table = chi-squared values, NOT probabilities. 35) J.A. Moore investigated the inheritance of spotting patterns in leopard frogs. The pipiens phenotype had the normal spots that give leopard frogs their name. In contrast, the burnsi phenotype lacked spots on its back. Moore carried out the following crosses, producing the progeny indicated. Parent Phenotypes Progeny phenotypes BICD-100 Genetics Ghiara Spring 08 Week 6- Tuesday Burnsi x burnsi 39 burnsi, 6 pipiens Burnsi x pipiens 23 burnsi, 33 pipiens Burnsi x pipiens 196 burnsi, 210 pipiens a) On the basis of these results, what is the most likely mode of inheritance of the burnsi phenotype? b) Give the most likely genotypes of the parents in each cross. c) Use a chi-square test to evaluate the fit of the observed numbers of progeny to the number expected on the basis of your proposed genotypes....
View Full Document

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern