First Assignment: Entry Assessment; Defining your Experimental Question and Summarizing your Experimental Design; Diagramming your Crosses; Submitting your data for instructor check
This assignment is due by the beginning of Lab 2.
Part 1: If you haven't already done so, please make sure that you have completed your on-line Entry Assessment on Survey Monkey at the two links provided on the course Lab Sakai site or on the Lab wiki Home page. Please complete this entry assessment before the second lecture and before you have started reading your textbook or the background information found in the lab wiki. You will be asked to take the same assessment again at the end of the course. You will receive 2.5pts when you email to your lab instructor the phrase found when you submit the completed longer survey. Keep in mind that this knowledge survey will not be graded, nor will you be penalize in any way for incorrect answers. Rather, it is designed to help us assess how much you knew before you took this course and how well Wellesley's genetics course teaches core genetics concepts compared to other institutions. Comparing your pre and post course results will help us know how to improve BISC219 for future students. Thank you for your valuable input.
BISC219, Genetics Lab, models investigative science. We cannot provide individualized materials for you to design experiments to investigate questions you come up with on your own because of cost, time constraints, and your inexperience in using some of the tools. Nevertheless, we want you to learn first hand this semseter how scientists use genetic principles and techniques to answer basic and nuanced questions about gene structure and function and how that knowledge can be applied more broadly and communicated to the scientific community. Although your instructors have defined the questions and designed the experiments that will be used to address those questions, you must be able to, at any point in an investigation, describe what you are doing (summary of the experimental design and where you are in the process of completing the experiments), why you are doing it (experimental question(s) and goals), and what it means if x happens versus y when you collect your data (have a hypothesis formulated from basic genetic principles or previous studies). Significant and continual outside study is required for those ambitions to be realized.
Part 2: Read all of the background information on C. elegans found in BISC219/F13:_Worm_Info and then read all of Series 1 (Lab1 and the Completion of Autosomal or Sex Linked Genes? part of Lab 2).
Part 3: Assess your crosses: If you have phenotypically wild type hermaphrodites and about 30% or more males, your crosses are likely to have worked and you have an F1 generation to assess for x-linkage. Look carefully at the phenotype of each strains F1 males. Remember that X-Linkage is determined from the F1 males only (not the parental males!!!)in each strain's cross progeny. If you found that all of the male cross progeny are mutants (either dumpy or uncoordinated in phenotype or both dumpy and uncoordinated), you have partially determined the answer to our investigative question: How are the two mutations in mutants MB1, MB2, and MB3 inherited? You have also now ruled out x-linkage in any strains that have a wild type male F1 generation. If you have ruled out X-linkage in any of the three strains, on what type of chromosome are the mutations located?
After you have completed the F1 assessment on the 3rd day after Lab 1, please email your lab instructor and let her know if your crosses worked and what you have learned: Does MB1, MB2, or MB3 show one or both mutations as x-linked? If the answer is yes, be sure to specific whether the strain(s) with the sex-linked mutation is in a dpy or unc gene or both.
Part 4: Before the beginning of Lab 2, please diagram the crosses for Series 1. There is a template for the cross diagram that you can download here: Media:Series 1 Template for CrossesF12.ppt and use for this part of your assignment. In addition, please submit a written narrative to explain Series 1. Include a concise statement of the overall topic and the experimental question(s) or goals. Also include a brief, but clear and thorough summary of how you are investigating this question experimentally. Include ageneral methods description: a summary statement about each cross through the F2 generation using the genetic nomenclature that we have explained to you. Explain in a narrative paragraph how the the data you have and will generate will allow you to answer your experimental question(s) and achieve your investigation's goals. Include phenotype, genotype and ratio information and relevant comparisons.
Assignment 1 Lab 1– 12.5 points
| || At or Above Standard || Below Standard || Possible|
| Entry Survey
|| Completed BISC219 Genetics Entry Survey before second lecture
|| Did not complete Genetics Entry Survey
| Preliminary Data
|| Submitted preliminary cross results to instructor by email before the 4th Day after Lab 1
|| Did not email preliminary cross results to instructor on Day 3 after Lab 1
| Topic |
& Experimental Question(s)
| Constructed a clear, concise, and accurate description of the overall topic, and the experimental question(s) or goals
|| Topic or Experimental question(s) missing, inaccurate, partially accurate; contains too much tangential information or is too simplified
| Diagram of Crosses
|| Cross outcomes through F2 of our work if both mutations autosomal and linked; both mutations autosomal and unlinked; Dpy mutation X linked and Unc mutation autosomal; Unc mutation X linked and Dpy mutation autosomal-all diagrammed accurately using proper nomenclature and giving predicted ratios of progeny genotypically and phenotypically. Use provided template.
|| One or more possible cross outcomes missing; one or more are inaccurate, omit information, or do not include accurate predicted ratios of progeny for genotype and phenotype.Did not use nomenclature requested.
| Narrative description |
of Experimental Design
| Constructed a clear, concise, and accurate GENERAL description of the experimental design.
|| Experimental design description missing, inaccurate, partially accurate; contains too much tangential Materials and Methods information or is too simplified
| Narrative description |
of Data Analysis
| Constructed a clear, concise, and accurate description of how you will use the information on the cross diagrams, including the phenotypic ratios of progeny from your crosses, to determine whether or not the two mutations observed in strains MB1, MB2, and MB3 are autosomal or sex-linked and, if both autosomal, to determine if the mutations are in the same linkage group or that they sort independently.
|| Data Analysis(s) description missing, inaccurate, partially accurate; contains too much tangential information, or is too simplified.