Onion roots are ideal for studying mitosis because onions have larger chromosomes than most plants, making the observation of cells easier. The roots of plants also continue to grow as they continue to search for water and nutrients. This also makes it easy to find cells in the roots of onion plants at different stages of mitosis.
The chromosomes in onion roots also stain dark, which makes them easy to see using light compound microscope. The observation of mitosis using onion roots is done in biology classes as a means demonstrating the stages of cell division. Apart from onion roots, ginger roots are also used.
The part of the roots that is placed on a microscopic slide is usually taken from the tips called the apical meristems. The onion root tips are where the growth and cell division of plants take place at a very fast rate, so the chance of being able to observe cells in all the five stages of cell division will be high.
Mitosis is the process of cell division where the chromosomes divide and create exact duplicates of itself. This cell cycle is important for the development, growth, regeneration and reproduction of most living things. The stages of mitosis are interphase, prophase, metaphase, anaphase and telophase.