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ERIC Number: EJ1204654
Record Type: Journal
Publication Date: 2019-Feb
Pages: 8
Abstractor: ERIC
ISSN: ISSN-0036-8555
A New Twist on DNA Extraction
Chowning, Jeanne Ting; Wu, Regina; Brinkema, Caren; Crocker, Wendy; Bass, Krystal; LaZerte, Debbie
Science Teacher, v86 n6 p20-27 Feb 2019
DNA extraction from strawberries is a well-known procedure that allows students to visualize DNA and to recognize that living things contain DNA (NHGRI 2018, Science Buddies 2013). In this article, the authors describe a modification to the traditional DNA extraction protocol that promotes student agency in experimental design and also emphasizes important social dimensions of argumentation. The lesson provides ample opportunities for students to engage deeply in the social dimensions of argumentation. First, small groups of students design their own DNA extraction protocols based on their knowledge of cell structure and the properties of biomolecules. Within each group, they collaborate to make claims about a procedure that they expect to be effective, providing reasoning for using certain materials in a certain order. After obtaining their results, they conduct a "lab meeting," in which each group presents its protocol, the rationale for its design decisions, and its results. Students engage in questioning and critiquing the approaches of others as they try to build a collective understanding of the most effective approaches. The lab meeting introduces a critical aspect of scientific argumentation, one that is often neglected in school settings: collaborative discussion, critique, and sense-making about procedures. This approach allows teachers to emphasize the central role of collaborative talk in science, as well as the social dimensions of scientific argumentation as students puzzle out the best procedures for repeating the experiment. Structures such as lab meetings help provide students with insight into the roles of argumentation and sense-making in professional scientific communities.
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Publication Type: Journal Articles; Reports - Descriptive
Education Level: High Schools; Secondary Education
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A