Determining Time Spent in Different Phases of the Cell Cycle
Touch here to go to mitosis link.
Answer the following:
How is growth in an organism is carefully controlled?
How is it possible to examine the cell cycle of cells in the tip of an onion root?
Is each phase distinct, i.e., do the phases change from one to another instantly?
Write a short description in the blanks that follow the drawings.
Interphase. _______________________________________________________________________
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Prophase. ________________________________________________________________________
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Metaphase. _______________________________________________________________________
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Anaphase. ________________________________________________________________________
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Telophase and cytokinesis. __________________________________________________________
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Define these terms below and enclose in your lab report.
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The assignment
Questions: What percent of time do cells spend in each phase of the cell cycle? Does the
percentage vary with the location or type of the cells in the organism? First pull up the
lab report format, then fill in the questions above, write a hypothesis, and follow the
procedure in the online lab. In this activity, you will be presented with cells from the tip
of an onion root. You will write up a lab report using the lab report format to turn in to
the teacher. This instruction sheet with the items complete above will be your pre-lab.
You will classify each cell based on 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. You can base your calculation on a total cell cycle of 24
hours. You must report your data (data table) and make a pie graph (analysis) comparing
the % time in each phase of the cell cycle. Then complete the conclusion and error
statements. UPLOAD YOUR COMPLETE REPORT TO YOUR STUFF IN MY BIG
CAMPUS. The online activity can be found here. Create a graph can be found here.
Interphase
number of cells
percent of cells
Prophase
Metaphase
SAMPLE
TABLE
SAMPLE GRAPH
Anaphase
Telophase
Total
36
100%