Facilitator Name: Andrew Larson
Subject(s): DNA/RNA/protein structure, the genetic code, gene expression
Course Name: Biology I
Project Description & Content Topics Addressed
In this project, students used models to better understand structure/ function relationships in biological molecules. The overall goal was to have students develop a better manipulable model as a learning tool to understand the structure of DNA, RNA or protein. Along the way, students learn the processes of DNA replication, transcription, and translation, and the effect of mutations.
A.Learning Goals: Content Knowledge & Skills Addressed (Standards)
- DNA structure
- DNA replication
- RNA structure
- Protein structure (primary, secondary, tertiary, quaternary)
- mutations (types and effects)
B.4.1 Develop and revise a model that clarifies the relationship between DNA and chromosomes in coding the instructions for characteristic traits passed from parents to offspring.
B.4.2 Construct an explanation for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.
B.4.3 Construct a model to explain that the unique shape and function of each protein is determined by the sequence of its amino acids, and thus is determined by the sequence of the DNA that codes for this protein.
Other skills being taught in this project include prototyping, the use of a decision making matrix, and working as a team.
B. Driving Question: How do the structures of biological molecules relate to the functions that they carry out?
C. Entry Event: Students were given examples of existing toys that model DNA, RNA, and protein (K’Nex, Tangles, and ball/ stick model kits) along with some written instructions (see attached.) After some initial time to play, I ask them to draw on prior knowledge and record Need to Knows (including from the instructions that accompany the kits.) The use of these toys was a recurring theme throughout the project as we built on and refined models for these types of molecules.
D. Benchmarks & Scaffolding: The Genetic Code-Benchmarks & Scaffolding
E. End Products & Deliverables
At the “end” of this project, students presented their prototype in a “charrette” format, with their peers standing around the model and offering their questions, likes, and wonders. It was a different sort of presentation because the presenters were at the center of the room and had no presentation tools other than their prototypes. We all agreed that we liked the format of the presentation.
F. Rubric: The Genetic Code-Rubric
Standards 4.1, 4.2, 4.3 are covered on the document below. Please note that all rubrics are continually being revised and improved.
G. Community Partnerships: The only community partners that we really sought out in this project were local fabricators that could fabricate a model molecule based on student designs. We didn’t get to that point (yet) but in future iterations of this project I suspect that we will.
Somewhat considered a community partner would be the conference (HASTI) mentioned above. The authentic hook used to engage students was the potential of being able to take their models to the conference to pitch to vendors in the exhibition hall. Though we didn’t get prototypes that were refined enough to take, I think we will in the future.
Authenticity & Relevance (Real-World Connections, Applied Learning, Active Exploration):
The problem is of models that do not adequately model the structure OR allow for the models to be used to better understand the underlying processes that take place in cells (such as DNA replication, transcription, and translation.) The challenge was presented to students in advance of HASTI, the annual meeting of Hoosier Association of Science Teachers, Incorporated, where the exhibition hall features the best in what’s new in science classroom tools.
Inquiry: Students were given access to the materials mentioned above and also others such as Legos, Pop Beads, and more. They were also given total freedom to bring in materials of their choice and were encouraged to experiment with them, as well as modify the existing materials, to better demonstrate the key features of molecules such as Hydrogen bonding, attraction of opposite charges, repulsion of polar and non-polar molecules, and self- assembly.
Student Voice & Choice: After having demonstrated proficiency of the standards, groups of students chose a molecule to model. There was a certain amount of differentiation by difficulty level, with DNA being the simplest and Protein being the most complex. Throughout the project, students had access to many different types of scaffolding materials and used them as needed to demonstrate proficiency of the content.
Employability (21st Century) Skills Addressed
- Critical thinking and problem solving
- Collaboration skills
- Oral communication
Employability (21st Century) Skills Rubrics
Required Materials and/or Tools:
- Various molecular modeling materials. We used ball and stick models.
- Protein Tangles
- K’Nex DNA model
- Other low- tech materials such as Legos (Lego Bionicles connectors work very well for proteins,) pipe cleaners, and velcro were brought in by students.
Examples of Student Work:
I have many pictures, but I can upload just one. It is an example of a very good protein model, where the individual amino acids were created using wooden beads. Students used pipe cleaners to thread through holes in the beads and magnets to allow parts of the model to link together, as real proteins do.
This group is experimenting with Legos to create a DNA model. While it was conceptually satisfactory, the use of Lego blocks did not effectively improve on the existing models available.