7th Graders Study Regeneration by Examining Planaria
As students of Life Science, 7th Graders are learning about living organisms, with a current focus on the question of how living things carry out cellular regeneration, the process by which an organism regrows damaged or missing parts/organs from the remaining tissue. For a hands-on look at how stem cells accumulate and divide to rebuild the missing part, students are examining planaria, freshwater flatworms with the ability to regenerate.
In their Planaria lab, 7th Graders first learned about this organism’s characteristics, movements, classification, nervous system and digestive system. Working in pairs, students examined a planarian in a petri dish using a handheld digital microscope. They found the average length of their planaria, tested whether the organism was touch sensitive and determined which parts seemed most sensitive. Next, students placed bits of egg yolk in the petri dish to observe if – and how – planaria are able to locate food.
After placing ice under the petri dishes to slow down their planaria’s movements, 7th Graders used a scalpel to amputate the organisms. Next week, students will observe their planaria for signs of regeneration, providing them with a first-hand experience of cellular regeneration that will inform their understanding of how and why this process occurs across every living species.