Name:______________________________________
Period:_____
Mitosis in Onion Cells
Background Questions
1. Which phase of the cell cycle takes the longest time?
2. Which phase of the cell cycle takes the least amount of time?
For each of the phases of the cell cycle and mitosis, write a brief
description of what the cell would look like (focus on
DNA/chromosomes).
Interphase
Prophase
Metaphase
Anaphase
Telophase
Stage/Phase
Picture 1
Picture 2
Picture 3
Interphase
120
86
63
Prophase
12
5
6
Metaphase
3
1
0
Anaphase
2
0
1
Telophase
2
0
0
Total Cells in
Picture
Total # of cells per % of time in each
phase
phase
Post-Lab Questions
1. What percentage of the cells that you observed were undergoing M phase (mitosis)?
2. Based on the number of cells observed in each phase of the cell cycle, which do you think
takes the longest amount of time to complete? The lease amount of time to complete?
Explain your reason.
3. What is the role of the cell cycle in the distribution of genetic information to new cells?
4. Refer to your circle graph: What changes occur in the nucleus of the cell during the longest
phase of the cell cycle?