Wednesday, November 3, 2010

Mitosis

Chromatin condenses into chromosomes happens in the prophase step. To get the cremation to condense the nucleolus has to fade.
Chromosomes align in center of cell happens in the metaphase step. To get the chromosomes to align, tension is applied by the spindle fibers.
The longest part of the cell cycle is the interphase. The reason it is so long is because DNA replicates, centrioles divide, and proteins are actively produced.
Nuclear envelope breaks down in the pro metaphase. When this happens, there is no longer a visible nucleus.
Cell is cleaved into two new daughter cells in the cytokinesis stage. Microtobules then reorganize themselves into a new cytoskeleton.
Daughter chromosomes arrive at the poles in the telophase. The spindle fibers have pulled them apart.

Four chromosomes are visible at the beginning of mitosis.

There are going to be eight chromosomes in each daughter cell at the end of mitosis.

The little green T shaped things on the cell are Centrioles.

During mitosis, the centrioles are no longer together in one cell. One of each go into the daughter cells.

The first stage is metaphase. The second stage is cytokinesis. The third stage is prophase.

View the animation and sketch the cell in:
Prophase
In the prophase stage, the cell(s) enlarges, and the chromosomes and centrioles replicate. It looks like a normal cell but with two centrioles, and two chromosomes. It does enlarge, too, but it is hard to notice.

Metaphase
In the metaphase stage, the chromosomes condense into much smaller x-like forms. The nucleolus dissolves, and spindle treads form. The centrioles, which are now duplicated, move to opposite sides of the cell.

Telophase
In the telophase stage, the chromosomes move to different sides of the cell, and they relax into their original forms. The spindle fibers dissolve, and the cell is pinched in two. Mitosis then stars over.

InterphaseProphaseMetaphaseAnaphaseTelophaseTotal

Number of cells

10 Cells3 Cells2 Cells1 Cell1636

Percent of cells

(calculate: number of cells divided by total cells x 100 )

62.5%18.9%12.5%6.3%33.3% of all cells (36)100 %



Mitosis in Whitefish & Onion Roots

View 1
View 2
View 3
View 4
View 5
Whitefish Telophase Metaphase Prophase Metaphase
Onion Metaphase Metaphase Prophase Prophase Telophase

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