Mitosis and Meiosis describes the process by which the
body prepares cells to participate in either asexual or sexual reproduction
to make an entire organism.
Examples of Mitosis and Meiosis
Mitosis is the reproduction of skin, heart, stomach, cheek, hair
etc. cells. These cells are "Autosomal" cells. This is also a form of
"Asexual" reproduction, where one organism or cell reproduces itself.
Some organisms that reproduce asexually are hydra, bacteria, and single
celled organisms.
"A" greek meaning "without."
- "Sex" Greek meaning "to cross."
Meiosis is the production of sperm and egg cells. These cells
are "Gamete" or "Sex" cells. Each cell has to go through the division
process twice in order for the cell to end up with half the number of
chromosomes. The cells pass on genetic information to the offspring. This
is a form of "Sexual" reproduction, where one organism or cells reproduces
by crossing with another organism or cell. Types of organisms that reproduce
sexually are; plants, animals, and insects.
- For either of these processes of reproduction we must first understand
the basic Chromosome structure that the body uses in either Mitosis
or Meiosis.

Mitosis: -- One cell becomes two cells-- The new
"daughter" cell has exactly the same number of chromosomes and information
as the "parent" cell. 1 cell divides and becomes 2 cells.

Meiosis: -- One cell becomes 4 cells--There are
4 new "daughter" cells. Each new gamete cell contains only one-half
of the number of chromosomes of the parent cell. Each sex cell goes through
the division process twice in order to have the correct number of cells,
and the correct chromosomal information. (Look carefully at the diagram
below to understand how each chromatid becomes part of a new sperm or
egg cell. Go back to the first diagram if necessary to study what a chromosome
pair, chromatid, and allele is.)

In female mammals (humans too) 3 of the gametes do not mature with a
full yoke sack. Only 1 of the 4 can become a mature egg. All mature eggs
are formed to a certain stage in the first division.
In male mammals (humans too) all 4 gametes mature into sperm cells. The
male is continually forming these after birth.
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