Over several days recently, Mount Madonna School (MMS) ninth grade students learned about cell osmosis, and their understanding of this concept was increased by participating in a hands-on activity known as the “Naked Egg Lab.”
The students began by placing eggs in vinegar to break apart the outer shell, leaving a semi-permeable membrane. Left in the vinegar, the eggs grew in size as the water from the vinegar enters the egg when the shell was removed, demonstrating osmosis: water moving from an area of high to low concentration.
“Students are frequently surprised to know that vinegar is 95% water. As its concentration of water is higher than that of the egg, the water goes into the egg,” explained teacher Nicole Silva. “After that they put the eggs into corn syrup and left them overnight. The next day the eggs were deflated and had hardly any water left in them.
“On the third day, students put them in colored water, where they swell back up,” she continued. “Students are learning about when a cell is in a hypertonic, hypotonic and isotonic state, and how important that is to our daily functions to maintain homeostasis and stay healthy. In this lab students write qualitative observations about the eggs, such as color and texture, as well as quantitative observations, like mass and percent change, each day.”
As students completed this “eggcellent” learning experience, they prepped for another project they will be doing while MMS is on a planned, temporary remote learning schedule following the holiday break. Their preparations included dismantling laser pointers to remove the lens, and then put the lens over the camera lens of their cell phones to make “homemade” microscopes.
“Using these homemade microscopes, said Silva, “students will be able to observe microorganisms furthering our study of the foundations of biology.”
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Nestled among the redwoods on 375 acres, Mount Madonna School (MMS) is a diverse learning community dedicated to creative, intellectual, and ethical growth. MMS supports its students in becoming caring, self-aware, discerning and articulate individuals; and believe a fulfilling life includes personal accomplishments, meaningful relationships and service to society. The CAIS and WASC accredited program emphasizes academic excellence, creative self-expression and positive character development. Located on Summit Road between Gilroy and Watsonville. Founded in 1979.