Cell
division allows organisms to:
-
reproduce
-
grow
-
repair
damage
Reproduction
-
Asexual
o It is a process of producing
offspring from only one parent to produce offspring that is genetically
identical to the parent.
o The cell divides into two identical
cells
-
Sexual
o It is a process of producing
offspring by fusing a cell from one parent with the cell from another parent.
o Each parent gives half of its
genetic information (23 chromosomes each) to produce a gamete through the
process of meiosis.
Growth
-
In
order for multi-cellular organisms to grow, they increase the number of cells
rather that increasing the size of the cell.
-
In
order for cells to function, they require:
o A source of energy, nutrients, water
and gases
o Must excrete carbon dioxide and waste
-
These
substances substances enter and exit the cell through DIFUSSION
o Movement from an area of high
concentration to an area of low.
-
Most
chemicals are dissolved in water, so cells must contains plenty of water
-
Water
enters and leaves cell through OSMOSIS
o The movement of water across a selectively
permeable membrane toward an area of high solute concentration.
-
Difussion
and osmosis must occur quickly.
o The chemicals should be available to
all parts of the cell in order to function properly.
o Wastes are removed before they
poison the cell.
Repair
-
The
process of mitosis also allows organisms to regenerate damaged tissues.
-
Mitosis
is also necessary for maintenance of the body
o Cells are replaced if not functioning
properly or when they die.
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