Download Mitosis Investigation

Name: ______________________
3U Biology –Cell Cycle Investigation - Making Connections
Background:
You are provided with either a slide of Allium (Onion) root tip or of a Whitefish embryo.
There are several cross-sections in each slide. It does not make any difference which one you
choose to look at first. Start, as always, at the lowest power, and observe the cells at the highest
magnification. Both slides show cells at the five stages of the cell cycle that were all frozen
(=killed) at the same time.
Note: the term Mitosis refers to the division of the cell’s nucleus. The subsequent division of the
cytoplasm is called Cytokinesis.
Procedure:
(i) Draw one labelled diagram of a cell in each stage of the cell cycle: Interphase, Prophase,
Metaphase, Anaphase and Telophase (Cytokinesis), five diagrams in all.
(ii) List the main events in each of the five stages.
(iii) Based on your observations, list the stages in decreasing length of duration, i.e. start with the
longest stage and the shortest stage should be the last one. Provide a rationale for your choice.
Questions:
1. Why were the cells in the onion root tip chosen for this slide? Which other parts of an onion
could have also been used? Give reasons for your answers to both questions.
2. Why were the whitefish embryo cells chosen for this slide?
3. List the differences between mitosis in animal and plant cells.
4. Provide definitions for the following terms: centriole, chromosome, chromatid, spindle fibre,
cytokinesis, and cell cleavage/furrow, cell plate.
5. List the names of five areas of the human body where cells undergo continuous mitosis.
6. List regions of a flowering plant that undergo continuous mitosis.
Due date for submitting labelled diagrams, the description of each stage, and the answers to the
questions: ____________.