Learning Target 6. Recognize the type of daughter cells formed through mitosis and their chromosome number as compared to the parent cell. 1-1

1-2 Chromosome Number Each species has unique chromosome #  no relationship to complexity Diploid--2n  2 copies of each chromosome (1/Mom & 1/Dad) (Homologous pairs) All somatic cells (body cells) are 2n Haploid--1n  1 copy of each chromosome (either Mom’s or Dad’s) Only gametes (sperm/eggs) are 1n

1-3 Mitosis (Animal Cells) After “S” phase replicates DNA Division of nucleus ONLY ! chromosome # stays constant Centromere divides  each chromatid becomes a daughter chromosome M checkpoint-stops if chromosomes not aligned Prophase Metaphase Anaphase Telophase

1-4 Prophase 5 “events”  memorize them! 1.Chromatin coils  chromosomes appear 2.Nucleolus disappears 3.Nuclear membrane disappears 4.Centrioles & asters appear  move to opposite poles of cell 5.Spindle fibers appear 1.Polar fibers  centriole to centriole 2.Kinetochore fibers  centriole to centromere

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1-6 Metaphase Kinetochore fibers push chromosomes to middle of cell

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1-8 Anaphase Kinetochore fibers separate  break centromeres  pull chromatids to opposite poles of cell Characteristic “V” shape

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1-10 Telophase Reverse of Prophase

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1-12 Mitosis—Plant Cells Mitosis in plant cells Same phases as animal cells Plants don’t have centrioles or asters

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1-14 Cytokinesis Cytoplasm divides after mitosis Animals  Cleavage “furrow” (edges in) Plants  Cell Plate (center out) Mitosis animation: ology/mitosis.html ology/mitosis.html

1-15 Image found 11/29/4 on

1-16 Mitosis in Prokaryotes Asexual reproduction (Binary Fission)  Cloning 2 identical daughter cells Single DNA strand duplicates  cell elongates, pinches in half

1-17 Benefits of Mitosis Genetically identical daughter cells Take advantage of good conditions rapidly Algal blooms