Observation of Onion Cells under a Foldscope

Hi everyone, I’m Manas, a 11th grader from Bangalore, India. I am particularly interested in studying the phenomena of patterning of flower petals using the foldscope.

Before analysing petal patterning, I wanted to work on a simple experiment with onion cells to help me understand the workings of a foldscope.

I peeled a few samples of onion cells from the same layer. I soaked the samples of onion cells in a beaker containing RO-filtered water for 30 minutes.

The images of the onion cells that I captured are shown below:

A large purple vacuole can be clearly observed, along with a faint nucleus in some pictures. I took this experiment further by soaking onions in a saturated salt solution. My goal was to understand the effect of osmosis on the microscopy pictures. Attached is the video of these cells while osmosis was taking place (32x):

Also attached are the images from the same video at different times:

As time progresses, the extracellular solution is seen to become more and more purple, making the cells paler, as expected.

Here are some pictures I took of other onion cells. This is not a part of the experiment, I just captured these images for fun!

This is my first experiment with the foldscope. I would be posting more content in the near future on patterning of flowers, using the foldscope.

Signing off,


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