Today we examined both onion skin cells and epithelial cheek cells using methylene blue stain and the oil immersion lens on our microscope. They were both fascinating, but the onion cells, in their geometric regularity, were particularly beautiful. They looked like panes of stained glass. Well, stained glass with nuclei and organelles.
We also had an interesting learning moment when Colin’s sketch did not quite match up with what was visible through the field of view. He said that he thought the spots he was seeing were debris, while I thought they were organelles. So I told him how in science you have to put down what you see, not what you think you should see. I suspect that this is a lesson we’ll have to reinforce quite a bit. It might be time to relate the sad tale of Andrew Wakefield, et al.