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Assessing the Initial State of Knowledge of First-Year Genetics Harvard University Assessing the initial state of knowledge 9 Oxford Street Cambridge, MA 02138 of first-year genetics students (617) 495-9616 Adam P. Fagen, Molecular Biology & Education (617) 496-4654 Fax Harvard University – http://mazur-www.harvard.edu/ [email protected] Motivation Genetics & Genomics Results Genetic code 100% 5 No standard inventory of conceptual First semester for a new introductory genetics 90% Students have a wide (0-5) 4 understanding in the biological sciences. course for all students majoring in biology or 80% variety of backgrounds. 70% 3 60% biochemical sciences.and prerequisite for Familiarity with understanding 2 Inventories in other disciplines have helped 50% higher-level biology courses. terminology distributed Evaluated 40% motivate the need for reform in undergraduate 1 30% among the class. science education (e.g., Force Concept 20% 0 1 2 3 4 5 10% Confident understanding Self-reported familiarity (1-5) Inventory, Astronomy Diagnostic Test, Okay understanding 0% fect fate Hazy understanding acid AMP code gene allele clone ef carrier diploid gamete Not always a clear chiasma clastron cell mutation evolution anaphase annealing Conceptual Chemistry Test). sequence cis-acting anticodon backcross eukaryote Word is vaguely familiar amino cyclic dominance autosomes centromere denaturation chromosome genetic endonuclease bacteriophage founder electrophoresis Totally unfamiliar correspondence frameshift consensus More vocabulary in introductory biology than 100% 100% between students’ in foreign language courses (Yager 1983). 90% 90% familiarity with 80% 80% 70% 70% terminology and Students find that they can get by with 60% 60% 50% 50% their actual 40% memorization of definitions and little 40% understanding. 30% 30% understanding of the underlying concepts. 20% 20% 10% 75% first-year students 10% 0% 0% blot end RNA Exams in introductory science courses tend gene probe zygote gene gene protein frame enzyme element intron spooling strand hybrid wildtype mutation primer telomere groove template linkage operon ribosome ribozyme recessive promoter testcross repressor meiosis nucleus plasmid sex-linked reaction genome replication sticky transgenic translation mutation mutation pedigree fragment chromatids selection genotype imprinting inbreeding chromosome population transcription transcriptase phenotype transfer metaphase polymerase Southern reporter recombination X silent major heterozygous reading chain lagging not to test conceptual understanding and 73% pre-med nondisjunction sister messenger RNA Okazki natural restriction hemizygous knockout nonsense reverse housekeeping transposable rarely ask open-ended questions. open 61% female polymerase semiconservative 56% have taken AP (mean score: 4.7) 1st or 2nd college science course for 74% R.E. Yager. 1983. J. Res. Sci. Teach. 20: 577-588. Post-test Future work At the end of the semester, a similar survey Complete analysis of aggregate post-test was administered to assess learning gains results. about the courses. Survey instrument Definitions Compare pre- and post-test responses Briefly define 18 terms on vocabulary Students show much greater familiarity with for individual students. Biological Sciences 50 – Spring 2001 Beginning of Semester Survey Familiarity with terminology list (including distractor "spooling") vocabulary and increased ability to define Adam Fagen (afagen@fas), one of the Teaching Fellows for this course, is doing research on biology and education, and is very interested in finding out about the background of Bio Sci 50 students. This survey is designed to collect information on your previous experience in biology. You can help the teaching staff gain Investigate correlations between survey a better sense of your preparation and experience by completing this survey. Your responses on this survey will have no bearing on your grade. However, you will positively affect your Rate familiarity with 87 common terms terms. own experience in the course by responding thoughtfully and honestly. responses, educational background, and Thanks for your feedback! in genetics from glossary of text and Terminology class performance. The following table contains vocabulary taken from the glossary in the back of the text and represent some two distractors ("clastron" and Students still hold misconceptions about the of the important terms in genetics. For each word, indicate your familiarity with the term in the context of biology and genetics (several have non-scientific meaning as well) on a 1-5 scale as shown. Remember that Concept questions we do not expect or assume you to know all – or even any – of these terms prior to the course. T T W W otally unfamiliar otally unfamiliar understanding understanding understanding understanding understanding understanding "spooling") on a 1-5 point scale: ord is v ord is v nature of genetic material (>10% do not How well do you Confident How well do you Confident familiar familiar Oka Oka Hazy Hazy Use results to inform the development of know these terms know these terms aguely aguely in the context of y in the context of y One multiple choice, one free biology/genetics ? biology/genetics ? report that genetic material is identical a conceptual inventory which diminishes allele 1 2 3 4 5 frameshift mutation 1 2 3 4 5 5 = Confident understanding response, and one three-part amino acid 1 2 3 4 5 gamete 1 2 3 4 5 anaphase 1 2 3 4 5 gene 1 2 3 4 5 annealing 1 2 3 4 5 genetic code 1 2 3 4 5 between cells). anticodon 1 2 3 4 5 genome 1 2 3 4 5 4 = Okay understanding data interpretation question. the impact of vocabulary. autosomes 1 2 3 4 5 genotype 1 2 3 4 5 backcross 1 2 3 4 5 hemizygous gene 1 2 3 4 5 bacteriophage 1 2 3 4 5 heterozygous 1 2 3 4 5 carrier 1 2 3 4 5 housekeeping gene 1 2 3 4 5 3 = Hazy understanding cell fate 1 2 3 4 5 hybrid 1 2 3 4 5 centromere 1 2 3 4 5 imprinting 1 2 3 4 5 chiasma 1 2 3 4 5 inbreeding 1 2 3 4 5 chromosome 1 2 3 4 5 intron 1 2 3 4 5 2 = Word is vaguely familiar cis-acting 1 2 3 4 5 knockout mutation 1 2 3 4 5 clastron 1 2 3 4 5 lagging strand 1 2 3 4 5 Background information clone 1 2 3 4 5 linkage 1 2 3 4 5 consensus sequence 1 2 3 4 5 major groove 1 2 3 4 5 cyclic AMP 1 2 3 4 5 meiosis 1 2 3 4 5 1 = Totally unfamiliar denaturation 1 2 3 4 5 messenger RNA 1 2 3 4 5 High school and college science diploid 1 2 3 4 5 metaphase 1 2 3 4 5 dominance 1 2 3 4 5 natural selection 1 2 3 4 5 electrophoresis 1 2 3 4 5 nondisjunction 1 2 3 4 5 endonuclease 1 2 3 4 5 nonsense mutation 1 2 3 4 5 coursework, previous experience Acknowledgements eukaryote 1 2 3 4 5 nucleus 1 2 3 4 5 evolution 1 2 3 4 5 Okazaki fragment 1 2 3 4 5 founder effect 1 2 3 4 5 open reading frame 1 2 3 4 5 in biology, expected major, Thanks to the students and teaching staff of Bio Sci 50, especially Prof. Daniel L. Hartl and Head demographic information Teaching Fellows Dr. David Mark Welch and Colin Meiklejohn for their support of this project. Thanks to Eric Mazur and the Mazur Group for assistance with the poster. http://mazur-www.harvard.edu.
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