Mitosis

Materials

Prepared slide of Onion root tip

Prepared slide of whitefish blastula

Microscope

Procedure

1.Obtain a slide of an onion root tip and examine it for the basic stages of mitosis. Refer to Figure 11.3 for comparison.

2.Draw and label each of the stages.

3.Obtain a slide of a whitefish blastula for observation of the stages of mitosis in an animal cell. Since early embryogenesis involves rapid cellular division, the whitefish blastula has long served as a model of mitotic division in animals. It also has the advantage of demonstrating clear spindle formation in the cytoplasm.

4.Using Figure 11.3A as a guide, draw and label all stages of mitosis, including spindle formation, in the whitefish blastula.

5.Compare the division of the cell (cytokinesis) from the onion root tip to that of the whitefish blastomeres.