All cells have a life cycle Cell Cycle

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All cells have a life cycle (Cell Cycle)
Mature and grow Carry out required
activities Reproduce These processes vary
depending on the cell
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Cell Cycle The cell cycle is an ordered set
of events, culminating in cell growth and
division into two daughter cells. The stages
are G1-S-G2-M. The G1 stage stands for "GAP
1". The S stage stands for "Synthesis". This
is the stage when DNA replication occurs. The
G2 stage stands for "GAP 2". The M stage
stands for "mitosis",and is when nuclear
(chromosomes separate) and cytoplasmic
(cytokinesis) division occur.
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Cell Cycle
G1
S
G2
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Cell Reproduction The cell is the basic unit
of life Contain DNA and other biochemicals
All cells carry out life activities In charge
of life processes All cells come from
pre-existing cells Undergo Cellular
Reproduction
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Cellular Reproduction A way in which 1 cell
divides into 2 cells Occurs in all
organisms Somatic Cellular Reproduction
Produces 2 cells that are clones 2 major
phases 1. Mitosis (division of nucleus) 2.
Cytokinesis (division of cytoplasm)
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Mitosis Occurs in 4 stages Allows
cells to pass on exact copies of their DNA.
1. Prophase 2. Metaphase 3. Anaphase 4.
Telophase
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Before cells can divide, DNA needs to
duplicate. In form Chromosomes Found in
pairs After DNA replicates, it Super Coils
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chromosomes (unduplicated) in parent cell at
interphase
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Mitosis
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Early Prophase Mitosis Begins

• Duplicated chromosomes begin to condense

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Late Prophase

• New microtubules are assembled
• One centriole pair is moved toward opposite pole
  of spindle
• Nuclear envelope starts to break up

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Transition to Metaphase

• Spindle forms
• Spindle microtubules become attached to the two
  sister chromatids of each chromosome

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Metaphase

• All chromosomes are lined up at the spindle
  equator
• Chromosomes are maximally condensed

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Anaphase

• Sister chromatids of each chromosome are pulled
  apart
• Once separated, each chromatid is a chromosome

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Telophase

• Chromosomes decondense
• Two nuclear membranes form, one around each set
  of unduplicated chromosomes

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Results of Mitosis

• Two daughter nuclei
• Each with same chromosome number as parent cell
• Chromosomes are in unduplicated form

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Cytoplasmic Division

• Usually occurs between late anaphase and end of
  telophase
• Two mechanisms
• Cell plate formation (plants)
• Cleavage (animals)

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Prophase
Metaphase
Telophase
Anaphase
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Metaphase
Prophase
Anaphase
Telophase
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Cell Plate Formation
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Animal Cell Division