Mitosis in Onion Root Tip

Dark blue spaghetti-like parts of cells are chromosomes undergoing mitosis (cell division). The individual blue round areas are the cell’s nucleus, and the rectangular or squarish lines are the cell walls. There are approximately 73 cells visible in the photograph.

Onion root is chosen for demonstration of mitosis since it is rapidly growing so there are lots of cells undergoing mitosis at any time. Also, they are easy to get, and relatively easy to prepare.