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Mitosis Timeline Activity
In this activity, you will examine a photograph of cells from the actively growing tip
of an onion root. You will examine each cell and determine what phase it is in. At the
end you will count up the cells found in each phase and use those numbers to
predict how much time a dividing cell spends in each phase.
(Recall from the Online Mitosis Lab: % cells in any phase equals number of cells in
phase divided by total number of cells; to find amount of time, simply multiply the %
cells in phases by 24 hours.)
Enter data in this table from the photograph at the end of this activity. Then answer
the questions. When you have completed your work submit it to the dropbox
entitled Mitosis Time Investigation
*There are approximately 61 cells visible in the final photograph. Some of the
empty 'cells' do not have a nucleus visible and are not included in the count.
Interphase
Prophase
Metaphase
Anaphase
Telophase
# of cells
% of cells in
each phase
% of time
in each
phase
during 24
hours
Once you have filled in the table answer the following conclusion questions.
1.
2.
3.
4.
5.
6.
.
What phase are most cells found in?
What type of cells undergo mitosis?
What happens during metaphase?
What is the purpose of the spindle fibers?
What is happening during interphase?
Explain how the process of mitosis helps an organism to grow in size.
Total
61*
100%
24
hours