Transcript Document

What is Mitosis?
• Mitosis: Cell division
involving somatic (nonsex) cells
• Involves only diploid cells
• Form of asexual
reproduction for some life
(bacteria & protista, fungi)
• End Result: Two
genetically identical
“daughter cells”
The Cell Cycle
• Defined:
Repeating set of
events in the life
of a cell
• 1) Interphase
– G1, S, G2
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2) Prophase
3) Metaphase
4) Anaphase
5) Telophase
Interphase
• Divided into 3 Stages:
• G1 Stage
– Normal function
performed
– Cell growth
– Organelles created
• S Stage
– Chromatin (DNA
strands) duplicated
• G2 Stage
– Cell growth
– Normal function
performed
Prophase
• 1st Mitosis Stage
• Chromatin (DNA
strands) coils into
chromosomes
• Nucleus dissolves
spilling the
chromosomes
• Spindle fibers
form
Metaphase
• 2nd stage of
mitosis
• Spindle fibers
attach to
centromeres of
each chromosome
• Spindle fibers pull
the chromosomes
to the cell’s
equator
Anaphase
• 3rd stage of mitosis
• Spindle fibers pull
½ the chromatids
to each end of the
cell
– Humans: 46
chromatids each
way
Telophase
• 4th stage of mitosis
• Spindle fibers
dissolve
• Chromatids unwind
into chromatin
• Nucleus reforms
• Cytokinesis:
division of the
cytoplasm
Name that Stage!
Name that Stage!
Name that Stage!
Name that Stage!
Name that Stage!
Quick Review
• Mitosis = the division of somatic (nonsex) cells
• Each stage has different characteristics
• End Result = Two identical diploid
cells