Hi! So some weeks ago I did a laboration in school where we had to make or own samples of onion root cells, in order to study the different phases of mitosis in a microscope. Orcein and hydrochloric acid was used when preparing the samples, to "soften up the cells" and do dye them. My questions are: 1. Why is orcein used? How does it dye the chromosomes? 2. Why is hydrochloric acid used? How does it "soften" the cells? Thank you!