Investigation: Mitosis

This mitosis investigation was created during the 2020 pandemic for remote learning. In previous years, biology students would view slides in the lab and analyze data on cancer and mitotic index.

This at-home activity only looks at the mitosis of onion cells and I plan to add cancer and mitotic index as a separate activity. I used a microscope camera to take photos of onion root slides where students can count the number of cells in each phase

Then they use those numbers to calculate the amount of time spent in each. Students currently need to click on a link to a Google folder that contains the five photos though I may eventually move them to something more interactive.

You are welcome to download them and use them in your own class or even add them to the google slides so students do not need to leave that page.

The activity contains introductory information on the types of cells that divide (embryos, meristems) and the phases of mitosis as a review. Students are shown how to identify the phases on the photographs of the root tips. Then they complete a table which counts the number of cells in interphase, prophase, metaphase, anaphase, and telophase.

A simple formula uses these numbers to calculate the time spent based on the known time it takes for these cells to complete the cell cycle (720 minutes).

For a more advanced activity that uses real slides, check out the lab on Mitosis and Cancer.

slide of cells
Onion root tip showing cells in mitosis.