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Date
Period
XBIO: Cell Division Internet Activity
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Go to the website: www.biology.arizona.edu/
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Look for the “Activity” column on the left hand side of the screen and click on the
Cell Biology Activity: Onion Root Tips
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Read the introduction and answer the following questions.
1. Cell growth is controlled by the ___________________________.
2. The onion root tip is a good place to observe the cell cycle. Why is this so?
3. What process do the pictures on the right hand side of the screen show you?
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Click NEXT to find out about each stage of the cell cycle and answer the following
questions.
DRAW A CELL IN EACH PHASE IN THE BOX PROVIDED.
4. Interphase: During Interphase the cell is getting ready for nuclear division.
Describe what is happening to the DNA during this phase.
Will you be able to clearly see the chromosomes during this phase? _______
5. Prophase: Explain what happens to the chromosomes during Prophase.
Are the chromosomes visible under the microscope during this phase? ______
What is happening to the nuclear membrane during Prophase?
6. Metaphase: You can recognize a cell in Metaphase easily because the
chromosomes are (where in the cell?)______________________.
Why is it critical that the doubled chromosomes line up precisely at the middle of
the dividing cell?
7. Anaphase: Describe the movement of the chromosomes during Anaphase.
8. Telophase: How many daughter nuclei are formed during Telophase? _______
Are the chromosomes visible inside each new nuclei? _______
What happens to the cell’s membrane near the end of telophase?
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Click NEXT to continue and to start the interactive activity.
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Read and follow the instructions titled “The assignment”. You will have to sort all of
the pictures first and then go back and count them.
Interphase
Prophase
Metaphase
Anaphase
Telophase
Total
Number of
Cells
36 Cells*
% of
Cells**
100%
*Make sure that your total number of cells equals 36 when you add all phases.
**% of Cells = Number of Cells x 100
36
9. In what phase were most of the root tip cells? ____________________
10. (circle A or B) This means that cells spend
A) most
B) least
of their time in this phase of cell growth.
11. The least number of cells were found in what phase? ___________________
12. (circle A or B) This means that during mitosis, cells spend
A) most
B) least
of their time in this phase.