BISC 219/F10: Assignment 1 Lab1

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Lab 1 Assignment: Entry Assessment; Defining your Experimental Question and Summarizing your Experimental Design; Diagramming your Crosses; Submitting your data for instructor check (12.5 pts)

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 link provided on the course Lab Conference in First Class. 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 this assessment again at the end of the course. To reward you for completing it twice, we will grant you 5 points (2.5pts for each completed assessment). Please email the phrase found when you submit the completed survey to your lab instructor to receive credit. Keep in mind that this knowledge test will not be graded, nor will you be penalize in any way for incorrect answers. Rather, it is designed to help us assess how well Wellesley's genetics course teaches core genetics concepts compared to other institutions and it will help us know how to improve BISC219 for future students. Thank you for your valuable input.

BISC219, Genetics Lab, models investigative science. Although 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 BISC_219/F10:_Worm_Info and then read all of Series 1 (Lab1 and the Completion of Autosomal or Sex Linked Genes? in Lab 2) found at BISC_219/F10:_Gene_Linkage & BISC_219/F10:_Lab_2.

Part 3: After you have assessed the results of your first crosses on the 3rd day after Lab 1, please email your lab instructor and let her know if your crosses worked and which strain (MB1, MB2, or MB3) has an x-linked mutation (is itdpy or unc?). 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. X-Linkage is determined from the F1 males only (not the parental males!!!)in each strain's cross progeny. If you found all male single mutants (either dumpy or uncoordinated in phenotype), you have determined the answer to the first of our questions in this Series 1 investigation: Which strain, MB1, MB2, or MB3 has one X-linked mutation and is that x-linked mutation unc or dpy? . You have also now ruled out x-linkage in the dpy and unc mutations in the other two stains. You now know they are all autosomal because the males in the F1 of those strains were wild type, just like the hermaphrodite F1 generation.

Part 4: At the beginning of Lab 2 (or before if you submit your work electronically), please submit a concise statement of the overall topic and the experimental question(s) or goals in Series 1. Also include a brief, but clear and thorough summary of how you are investigating this question (general methods description and flow diagram of each cross through the F2 generation, using standard genetic nomenclature that we have explained to you and including phenotype, genotype, and ratios. Explain in a narrative how those cross diagrams you have created and the data you generate will allow you to answer your experimental question(s) and achieve your investigation's goals. There is a template for the cross diagram that you can download here: Media:Template for Crosses.ppt

Grading Rubric

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 2.5 __/2.5
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 1 __/1
& 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 1 __/1
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. 4 __/4
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 1 __/1
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. 3 __/3
Total 12.5 __/12.5