What can we learn from worms? How the nematode C. elegans maintains balance in a changing environment
C. elegans is a well-studied model organism used in research on genetics, development, and behavior. In this unit, students conduct an experiment comparing the effect of elevated salt in the environment on wild type worms and a mutant that is resistant to higher salt concentrations (or osmolarity, referred to as an OSM strain). Through this hands-on unit, students set up the experiment, make observations, analyze their results and other scientific evidence, and develop a model that explains their results. These activities guide students in learning how worms maintain homeostasis in an unfavorable environment caused by high osmotic stress and help them build an understanding of how genes and environment interact to determine traits.
This curriculum supports the Next Generation Science Standards (NGSS) with particular emphasis on high school disciplinary core ideas LS1.A feedback mechanisms maintain internal conditions and mediate behavior, LS3.B how environmental factors affect expression of traits, and LS4.B how trait variation leads to differences in performance among individuals. Student also participate in science and engineering practices and are exposed to crosscutting concepts throughout the unit. Each lesson provides connections to the three dimensions of the NGSS.
Now available as an interactive website with embedded videos, comprehension questions, and assessment!
Download the following materials here:
SEATTLE PROTOCOL curricular materials using only wild type worms
GSEO Protocol: What can we learn from worms? one-page overview
Entire What can we learn from worms? curriculum
Materials list and instructions for maintaining worm stocks
Want to know how to chunk worms? Ayah will show you how.
Short videos showing wild type and mutant worms on high and low salt at different time points can be found here: (Videos best viewed using Internet Explorer)
| Time | Wild type on low salt | Wild type on high salt | Mutant on low salt | Mutant on high salt |
|---|---|---|---|---|
| 15 min | View | View | View | View |
| 24 hour | View | View | View | View |
| 48 hour | View | View | View | View |