Get out your copy

of the “Mitosis

and Cytokinesi

s” handout.

Stage Description of Stage Pr

opha

se

Example Drawings Plant Cell Animal Cell

Phases of Eukaryotic Mitosis

First and longest phase of mitosis. The nuclear envelope dissolves (goes away), chromatin coils up and condenses to form visible chromosomes.

Stage Description of Stage M

etap

hase

Example Drawings Plant Cell Animal Cell

The short second phase of mitosis. The doubled chromosomes become attached to the spindle fibers at their centromeres and move to the equator of the cell.

Phases of Eukaryotic Mitosis

Stage Description of Stage A

naph

ase

Example Drawings Plant Cell Animal Cell

The 3rd phase of mitosis. During this phase, the centromeres split and the sister chromatids are pulled to opposite poles of the cell by the shortening of the microtubules.

Phases of Eukaryotic Mitosis

Stage Description of Stage T

elop

hase

Example Drawings Plant Cell Animal Cell

The final phase of mitosis. Two distinct daughter cells are formed and the cells begin to separate. This stage is indicated by the formation of a cell plate in plant cells and a cleavage furrow in animal cells.

Cell Plate

Cleavage Furrow

Phases of Eukaryotic Mitosis

Why is Cytokinesis important?

Cytokinesis is the division of the cells cytoplasm and all the

cellular organelles that it contains (remember ribosomes,

lysosomes, endoplasmic reticulum, Golgi apparatus, and

mitochondria)

Mitosis guarantees genetic continuity. When mitosis is complete, unicellular organisms remain as single cells, In

multicellular organisms cell reproduction results in cells that work

together as tissues tissues work together to form organs organs to

form organ systems and organ systems form organisms.

Phases of Eukaryotic Mitosis

Break into lab groups and look at

the stages of mitosis in plant and animal cell cards at

your lab tables. Without using your

notes, see if you can arrange them in the correct mitotic

order.

Now use your notes to check your arrangements.

Mow lets look at the “Mitosis In An Onion Root Tip” sheet located on your lab table.

Create a data table similar to the one

below in your biology notebook.

Count the number of cells in each phase of

mitosis and enter the

numbers in your data table.

Enter your data on the spread sheet on the

teacher computer

Analysis Questions

Which phase showed the largest number of active cells?

Explain why this phase, of all the phases, would most likely have the most abundant number of active cells.Were some of the cells difficult to

classify into a particular stage of mitosis?

Explain why or why not.

Share your analysis with at lease two other lab

groups.