Download cell division

CELL DIVISION
PHASE 1
Interphase
Chromosomes appeared as threadlike coils called chromatin. In animal cells, two
structures called centrioles can be seen outside the nucleus. Centrioles play a
part in cell division. Chromosomes are copied, the number of chromosomes
doubles. Each chromosome and its sister are attached to the centromere. Now
the sister chromosomes are called chromatids.
PHASE 2
Prophase
Mitosis begins. Centrioles begin to move to opposite ends of the cell. A spindle
begins to develop between the two centrioles forming a “bridge” between
the opposite ends. At the end, the nuclear membrane begins to break down.
At the same time, the nucleolus in the nucleus disappears.
PHASE 3
Metaphase
Chromosomes attach to the spindle. Chromosomes are attached to the spindle by
the centromere, which still connects each chromatid to its identical sister
chromatid. It looks like the “World Globe”.
PHASE 4
Anaphase
Chromosomes begin to separate. Now the centromere splits and the sister
chromatids separate from each other. Each chromatid from each pair of sister
chromatids move to opposite ends along the spindle. Now the chromatids are
again called chromosomes.
PHASE 5
Telophase
Two new nuclei form. Chromosomes begin to uncoil and lose their rodlike
appearance. Now they again appear as chromatin and cannot easily be
distinguished. A nuclear membrane forms and the nucleolus reappears in each
cell.
PHASE 6
Cytokinesis
The cytoplasm divides in the cell. In plant cells, the cytoplasm is divided
by a cell plate, which will become the new cell membrane and a cell wall also
forms around each daughter cell.