Mitosis Cell Division

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Transcript Mitosis Cell Division

Mitosis
Cell Division
Why do cells undergo Cell Division?
Cell size- larger cells are less efficient,
cells divide to keep cells small
Growth of an organism- the more cells an
organism has, the larger it is. All multicelled
life starts as a single cell after fertilization
then grows.
Reproduction- single celled organisms
divide by Mitosis to reproduce.
Cell Life Cycle
Interphase- the phase a cell stays in
longest. Time of growth, DNA
replication and preparation for division
Mitosis- Actual time of cell division.
Nuclear division and separation of
chromosomes.
Cytokinesis-final phase of division
where cytoplasm is divided and cell
splits in two.
Cell cycle:
Overview of Mitosis Phases
Prophase- DNA has already
replicated. Nuclear Membrane
dissolves and Chromosomes shorten
and thicken. Centrosomes separate
and move to opposite ends of the cell.
Overview of Mitosis
Metaphase- Chromosomes have
aligned themselves along the equator
of the cell. Spindle fibers are present.
Overview of Mitosis
Anaphase- Phase in which the
chromosomes begin to separate and
move apart. Chromosomes are pulled
by the spindle fibers toward the
centrioles.
Overview of Mitosis
Telophase- The last phase of Mitosis.
Nuclear membranes re-form around
the new nuclei. Chromosomes
lengthen and become invisible. In
animal cells cleavage furrow forms, in
Plants, a Cell Plate
Cytokinesis- Final stage of the cell
Life Cycle
Cytoplasm and its contents are
divided and the original cell pinches
into two new daughter cells.