Howdy! On Thursday 13th of August, we used microscopes to look closely at the plant cells of an onion.
AIM:
The aim of this very experiment was to learn how to use a microscope (and the different parts of a microscope) but most importantly see the cells/the onion closer!
Equipment
The equipment we used was a microscope, glass slide, glass cover, iodine, a light and of course, the onion itself.
The method:
We first set our microscope, and plugged in our light. Next, we took a glass slide and from there, Mr Heath cut a small/thin piece of onion skin. We placed the thin layer of onion onto the glass slide, and carefully flattened it with tweezers. After that, we placed 1-2 drops of iodine (I will explain why later), and CAREFULLY placed the glass cover onto the onion skin so that there wouldn’t be any air bubbles, as if there were too many we wouldn’t be able to see our specimen! We placed it onto the stage, and meticulously shined the light onto the mirror part on the microscope so we could see our specimen. We also had to adjust with the course focus knob as we couldn’t see it straight away and and had to look for it.
The reason we had to use iodine was so that we could see the onion skin as it was practically translucent because of how thin the skin was. The iodine acts like a dye so we can see it.
RESULTS
If I’m gonna be honest? It looks like my nan’s toe. Well, if you don’t know what my grandma’s toes look like, the onion skin looked like a weird textured brick wall. It also made me gag. But it was kinda orange-ish and I could see some cells.
Discussion
The different parts of a plant cell are the cell wall, cell membrane, chloroplast, mitochondria, cytoplasm, and the nucleus. (Also the DNA inside.)
I could see like the cells of the onion, but not specific parts. (They just looked like weird clear-ish blobs)
Parts of a microscope are also the eye piece lens, the neck, the stage, the stage clips, the base, the fine focus knob, the course focus knob, the objective lens, and the mirror (which was for the light.)
CONCLUSION
Yes, it did work. I also successfully didn’t get ANY iodine on my fingers, as it takes about 1-2 weeks to get the stain off.. I wouldn’t really change anything as I think we did most things right.