Mitosis

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Mitosis Worksheet – Answer the questions about the photos below:

Onion root tip photos at 600X and 1000X taken by Stan Carpenter of Hands-On Labs, Inc.

1. What phase is this cell undergoing?

2. What happens after this phase?

1. The two center side-by-side cells are undergoing two different phases of mitosis.

a. What are these phases?

b. What diagnostic features can help you with your decision?

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Experiment Mitosis

1. What phase is this cell undergoing?

2. How can you tell?

1. This cell has clearly visible chromatids.

a. What’s the next phase this cell will undergo?

b. Where will the chromatids go in the coming phase?

1. The cell in the lower center is exhibiting signs of what phase of mitosis?

2. What phase does it appear the cell above is undergoing?

1. Explain what happens during anaphase.

2. When the chromatids separate, what is each called?

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Experiment Mitosis

Questions A. What is the purpose of mitosis?

B. Why is the cell cycle important for organisms?

C. What role does mitosis play in the growth of an embryo?

D. What is one main difference in the mitotic processes between plant and animal cells?

E. If the cell that has undergone mitosis originally had the diploid (2n) number of chromosomes, then what number of chromosomes will the nuclei in the two new cells have?

F. Can mitosis ever be used for reproduction?

G. What parts of plants are most impacted by mitosis?

H. Why might mitosis be easier to study in the tip of the root?

I. Where else in a plant might you find a large amount of mitotic cell division occurring?

J. How might the mitotic index be applied in agriculture?

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Experiment Mitosis

K. What did you compute to be the mitotic index of the combined six slides (assume there are 54 total cells)? In comparison to the indexes reflected in Figure 8, from approximately which area of a root was the sample taken?

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Experiment Mitosis