Mitosis and Asexual Reproduction Notes

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Mitosis and Asexual Reproduction Notes

• To be used with Mitosis and Asexual Reproduction
  Guided Notes

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Cell Reproduction

• All of your body (somatic) cells are formed by
  mitosis
• Cell Reproduction is important when our bodies
  grow or when certain cells need replacement
• Cell type Life span (days)
• Brain 30-50 years
• Red blood
• Platelets
• Stomach lining
• Liver
• Intestine lining
• Skin

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10
2
200
3
20
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Stem Cells - cells taken from an early stage
embryo that can differentiate (change into
different cells)
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Chromatin-Chromatid-ChromosomeGenetic material -
Contains DNA

• Chromatin Chromatid Chromosome
• DNA stands Coiled chromatin
  Replicated spaghetti meatballs sister
  chromatids

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The Cell Cycle - IPMAT2 Parts Interphase
Mitosis
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The Cell Cycle - IPMAT

• Interphase
• Prophase
• Metaphase
• Anaphase
• Telophase
• Cytokenesis

Cell cycle
Mitosis
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Interphase

• 3 parts of Interphase
• takes up about 90 of cell cycle
• G1 (growth one phase)
• organelles grow
• S (synthesis phase)
• replication of chromosome material
• G2 (growth phase two)
• more organelle and cell growth

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Interphase

• Chromatin
• Immature chromosomes. Chromosomes are NOT
  distinguishable under microscope.
• Chromatin looks like
• spaghetti meatballs.

CENTRIOLES
CHROMATIN
NUCLEAR MEMBRANE
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Mitosis - 4 phases

• Mitosis is the second part of the cell
• cycle and is a type of cell division that
• results in two identical daughter cells.
• The chromosome number in the daughter
• cell is the same as in the parent.
• - Humans have 46 chromosomes in each
• parent cell - their daughter cells will have
• 46 chromosomes.
• Also called asexual reproduction
• or nuclear cell division
• Only one parent is needed

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Mitosis Each species has a specific chromosome
number.

• Organism Number of Chromosomes
• Human
• Chimpanzee
• Dog
• Fruit fly
• Garden pea
• Adders fern
• Is the chromosome number related to the
• complexity of the organism??? NO WAY!

46
48
78
8
14
1260
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Phase1- Prophase

• 1. centrioles begin to separate
• 2. centrioles are connected by spindle fibers
  made of protein
• 3. nuclear membrane disappears
• 4. chromosomes appear coiled and
• become visible

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Chromosome Structure

• chromatid is one strand of a chromosome.
• two chromatids one chromosome
• centromere holds the chromatids together

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Phase 2 - Metaphase

• 1. centrioles move to opposite
• poles of the cell connected
• by the spindle fibers.
• 2. each chromosome moves
• to the center of a cell along
• one spindle fiber.
• 3. the centromere attaches to
• a specific spindle fiber.

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Phase 3 - Anaphase

• 1. cell is egg shape
• 2. centromeres replicate
• separate
• 3. chromosomes separate
• 4. cytoplasmic division begin
• 5. cell membrane begins to pinch in

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Phase 4 - Telophase

• 1. cell shape is figure 8
• 2. spindle fibers disappear
• 3. nuclear membrane reforms
• around chromosomes
• 4. centrioles replicate in late
• telophase
• 5. cell division begins in late
• telophase

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Cytokenesis--known as complete cell
division-two identical daughter cells
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The Cell CycleInterphase Mitosis
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Mitosis
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Plant Mitosis

• How does mitosis differ in plants?
• No centriole in plant cells
• Plant cells do not pinch in half
• Cytoplasmic division is accomplished by a cell
  plate forming between 2 daughter cells

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Mitosis In Plants Interphase
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Mitosis In Plants Prophase
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Mitosis In Plants Metaphase
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Mitosis In Plants Anaphase
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Mitosis In Plants Telophase
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Mitosis In Plants Interphase
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Results of Mitosis

• The same chromosome number is retained from
  generation to generation
• Each daughter cell receives an exact copy of the
  chromosomes of the parent cell

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Results of Mitosis

• 3. Mutations are rare
• Cancer uncontrolled cellular
• mitotic divisions
• Causes Environment influences
• Viruses
• Smoking
• Radiation
• Prevention Diet exercise

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Methods of Asexual Reproduction

• Binary fission equal division of the cytoplasm
  and nucleus
• results in two new organisms
• Examples paramecium, ameba, euglena

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Methods of Asexual Reproduction

• Budding nucleus of an organism's cell divides
  equally but the cytoplasm divides unequally
• Examples yeast, hydra, Sponge Bob

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Sponge Bob
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Methods of Asexual Reproduction

• Sporulation the production of spores
• Example molds
• spores single, specialized cells which are
  released from the parent
• they are enclosed in a protective case and
  develop when environmental conditions are
  favorable

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Sporulation
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Methods of Asexual Reproduction

• Regeneration the development of an entire new
  organism from part of an original organism
• Example starfishone ray and part of central
  body
• may also involve the restoration of lost body
  parts
• invertebrates have greater powers of regeneration
  than do vertebrates

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Regeneration
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Patrick
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Methods of Asexual Reproduction

• Vegetative Propagation regeneration in plants
• Complete new plants develop from part of the
  original plant
• Example Grafting

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Asexual Reproduction Summary

• Individuals produced during asexual reproduction
  are genetically identical to their parents