In this virtual lab activity, you will be observing the cell cycle in the tip of an onion root. The root tip is responsible for the downward growth of the root and is one of the regions in the plant where cells are actively dividing and growing. Because of this, the root tip is an excellent system in which to observe the entire cell cycle, including the processes of nuclear division (mitosis) and cell division (cytokinesis).
You will be submitting a lab report as the assignment for this lesson. Be sure to read the instructions before completing the virtual lab activity and your lab report. Refer to the lab rubric before you submit your report to your instructor.
Cell Cycle Lab
Safety Notes:
Always handle microscopes and glass slides carefully.
Wash your hands after handling the prepared specimens.
Materials:
Compound Light Microscope
Glass microscope slide with prepared onion root tip specimen
Purpose: understand and identify the stages of the cell cycle and mitosis. apply an analytical technique to estimate the relative length of each stage of the cell cycle.
Hypothesis:
Procedure:
Data and Observations:
Create a data table containing a tally of the number of cells observed in each of the following stages:
Stage
Number of Cells in Part 1
Number of Cells in Part 2
Interphase
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis
Record any observations about the cells you observed:
Data Analysis:
Calculate the percentage of the cell cycle spent in each stage.
Number of cells in given stage ÷ total number of cells counted × 100 = % of the cell cycle spent in this stage
Create a graph that represents the time spent in each stage of the cell cycle.
Graph:
Conclusion:
Be sure to answer the following reflection questions in the conclusion of your lab report:
1 Based on your data, what can you infer about the length of time spent in each stage of mitosis?
2 What stages