The Pasta Model of Bone Part of: Inquiry Science with Dartmouth (a new program!) Developed by Justine Hutchinson for Erica Ferland’s Anatomy and Physiology Class Steven’s High School, Claremont, NH Adapted from NIH Looking Good, Feeling Good: From the Inside Out Lesson 2: What Makes Bones Strong? Overview This lesson includes a hands-­‐on exploration of the structure and function of bone. Science Standards NSES Content Standard A: Different kinds of questions suggest different kinds of scientific investigations; some involve making models. NSES Content Standard A: Use appropriate tools and techniques to gather, analyze, and interpret data. NSES Content Standard C: Specialized cells perform specialized functions in multicellular organisms. New Hampshire State Standards S:LS1:8:2.4 Explain relationships between or among the structure and function of the cells, tissues, organs, and organ systems in an organism. [LS1(5-­‐8)FAF-­‐4] S:SPS2:8:3.2 Know that different models can be used to represent the same thing; what kind of model is used and how complex it should be depends on its purpose; and the usefulness of a model is one of the instances in which intuition and creativity come into play in science, mathematics and engineering. Focus Question: What makes bones strong? Objectives Through this lesson, students will: • Be able to name the major components of bone tissue: o calcium minerals o collagen fibers (proteins) o cells • Be able to explain how a pasta model demonstrates the contributions of collagen and minerals to bone strength. Background This is a good first lesson on the musculo-­‐skeletal system. For grades 6-­‐10, it is important to have covered the differences between living and non-­‐living systems. For grades 11-­‐12+, this lesson should build on a unit on cells and tissue types (e.g. Marieb chapter 3). Vocabulary Tissue: A group of cells in an organism sharing a common structure and similar functions. Hydroxylapatite: Calcium combines with phosphate to make the hard material, or mineral, in bone. Collagen fibers: Collagen is a fibrous protein, long and insoluble, found in skin, tendon, cartilage, and bone. Materials (per group of 2-­‐3 students) o 50 pieces of pasta o 5-­‐10 rubber bands o a ruler o a paper clip o a weight (50-­‐200 g) o 2 blocks or stacks of books o data sheet and pencil for recording results Preparation Optional: Soak a chicken bone in vinegar for two days before the lesson. Procedure – This is what you will do during class. Include estimated time for each section 1. Introduction: I am a cell biologist. I work in a lab that studies development in mammary tissue in order to discover new treatments for breast cancer. Today, we are going to do some experiments that will introduce you to the idea of development in a related tissue, bone! 2. Hook: Bones are very important! How do they do so many different things? 3. Background: Bones are made of cells, calcium minerals, and 4. Experiment: Measure the displacement of a pasta model of bone with and without rubber bands representing the crosslinks between collagen fibers. 5. Data collection: This may be part of the experiment or in addition to the earlier sections. You may want to design a handout or data collection sheet to go with this. 6. More Experimentation: Soak bundled pasta in water for two minutes to represent the strength of collagen without calcium. 7. Share: Have groups share the results of their study. 8. Optional Demonstration: What happens when we soak a chicken bone in vinegar to leach out all of the calcium? 9. Lesson/wrap: Show the bathtub slide. Talk about bone cells and how they respond to signals. “Bone Morphogenic Protein” or BMP is a signal that was discovered in bone, and we are studying the role of BMP in breast cancer. Assessment Is the data sheet filled out? Additional Questions: What does the unbundled pasta represent? What do the bands represent? What did the soaked pasta represent? Would bone be as strong if the collagen proteins couldn’t be linked to each other? Extensions At the middle school level, this module could prepare students for the study of nutrition and human health. At the high school level, this module could prepare students to learn about bone remodeling, bone development, and/or the effects of hormones on bones. Bibliography: http://science.education.nih.gov/customers.nsf/MSBone.htm Marieb chapter 3 (cells and tissues) and chapter 5 (skeletal system).